From 38b704384cd2f17590b3922b97744be0b43622c9 Mon Sep 17 00:00:00 2001
From: nik7273 <nik8470@gmail.com>
Date: Fri, 8 Mar 2019 10:27:53 -0500
Subject: Changed HTTP URLs to HTTPS where possible (#270)

---
 absl/debugging/leak_check.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'absl/debugging/leak_check.h')

diff --git a/absl/debugging/leak_check.h b/absl/debugging/leak_check.h
index c930684e..4d489c58 100644
--- a/absl/debugging/leak_check.h
+++ b/absl/debugging/leak_check.h
@@ -4,7 +4,7 @@
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
-//      http://www.apache.org/licenses/LICENSE-2.0
+//      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,
-- 
cgit v1.2.3


From 12bc53e0318d80569270a5b26ccbc62b52022b89 Mon Sep 17 00:00:00 2001
From: Abseil Team <absl-team@google.com>
Date: Thu, 12 Dec 2019 10:36:03 -0800
Subject: Export of internal Abseil changes

--
c99f979ad34f155fbeeea69b88bdc7458d89a21c by Derek Mauro <dmauro@google.com>:

Remove a floating point division by zero test.

This isn't testing behavior related to the library, and MSVC warns
about it in opt mode.

PiperOrigin-RevId: 285220804

--
68b015491f0dbf1ab547994673281abd1f34cd4b by Gennadiy Rozental <rogeeff@google.com>:

This CL introduces following changes to the class FlagImpl:
* We eliminate the CommandLineFlagLocks struct. Instead callback guard and callback function are combined into a single CallbackData struct, while primary data lock is stored separately.
* CallbackData member of class FlagImpl is initially set to be nullptr and is only allocated and initialized when a flag's callback is being set. For most flags we do not pay for the extra space and extra absl::Mutex now.
* Primary data guard is stored in data_guard_ data member. This is a properly aligned character buffer of necessary size. During initialization of the flag we construct absl::Mutex in this space using placement new call.
* We now avoid extra value copy after successful attempt to parse value out of string. Instead we swap flag's current value with tentative value we just produced.

PiperOrigin-RevId: 285132636

--
ed45d118fb818969eb13094cf7827c885dfc562c by Tom Manshreck <shreck@google.com>:

Change null-term* (and nul-term*) to NUL-term* in comments

PiperOrigin-RevId: 285036610

--
729619017944db895ce8d6d29c1995aa2e5628a5 by Derek Mauro <dmauro@google.com>:

Use the Posix implementation of thread identity on MinGW.
Some versions of MinGW suffer from thread_local bugs.

PiperOrigin-RevId: 285022920

--
39a25493503c76885bc3254c28f66a251c5b5bb0 by Greg Falcon <gfalcon@google.com>:

Implementation detail change.

Add further ABSL_NAMESPACE_BEGIN and _END annotation macros to files in Abseil.

PiperOrigin-RevId: 285012012
GitOrigin-RevId: c99f979ad34f155fbeeea69b88bdc7458d89a21c
Change-Id: I4c85d3704e45d11a9ac50d562f39640a6adbedc1
---
 absl/algorithm/BUILD.bazel                         |   1 +
 absl/algorithm/CMakeLists.txt                      |   2 +
 absl/algorithm/algorithm.h                         |   4 +
 absl/algorithm/container.h                         |   2 +
 absl/base/internal/raw_logging.h                   |   2 +-
 absl/base/internal/thread_identity.h               |   2 +-
 absl/container/BUILD.bazel                         |   8 ++
 absl/container/CMakeLists.txt                      |   8 ++
 absl/container/btree_map.h                         |   2 +
 absl/container/btree_set.h                         |   2 +
 absl/container/btree_test.cc                       |   2 +
 absl/container/btree_test.h                        |   2 +
 absl/container/fixed_array.h                       |   2 +
 .../container/fixed_array_exception_safety_test.cc |   2 +
 absl/container/flat_hash_map.h                     |   2 +
 absl/container/flat_hash_map_test.cc               |   2 +
 absl/container/flat_hash_set.h                     |   2 +
 absl/container/flat_hash_set_test.cc               |   2 +
 absl/container/inlined_vector.h                    |   2 +
 absl/container/internal/btree.h                    |   2 +
 absl/container/internal/btree_container.h          |   2 +
 absl/container/internal/common.h                   |   2 +
 absl/container/internal/compressed_tuple.h         |   2 +
 absl/container/internal/compressed_tuple_test.cc   |   2 +
 absl/container/internal/container_memory.h         |   2 +
 absl/container/internal/container_memory_test.cc   |   2 +
 absl/container/internal/counting_allocator.h       |   4 +
 absl/container/internal/hash_function_defaults.h   |   2 +
 .../internal/hash_function_defaults_test.cc        |   4 +
 absl/container/internal/hash_generator_testing.cc  |   2 +
 absl/container/internal/hash_generator_testing.h   |   2 +
 absl/container/internal/hash_policy_testing.h      |   2 +
 .../container/internal/hash_policy_testing_test.cc |   2 +
 absl/container/internal/hash_policy_traits.h       |   2 +
 absl/container/internal/hash_policy_traits_test.cc |   2 +
 absl/container/internal/hashtable_debug.h          |   2 +
 absl/container/internal/hashtable_debug_hooks.h    |   4 +
 absl/container/internal/hashtablez_sampler.cc      |   2 +
 absl/container/internal/hashtablez_sampler.h       |   2 +
 .../hashtablez_sampler_force_weak_definition.cc    |   2 +
 absl/container/internal/hashtablez_sampler_test.cc |   2 +
 absl/container/internal/inlined_vector.h           |   2 +
 absl/container/internal/layout.h                   |   2 +
 absl/container/internal/layout_test.cc             |   2 +
 absl/container/internal/node_hash_policy.h         |   4 +
 absl/container/internal/node_hash_policy_test.cc   |   2 +
 absl/container/internal/raw_hash_map.h             |   2 +
 absl/container/internal/raw_hash_set.cc            |   2 +
 absl/container/internal/raw_hash_set.h             |   2 +
 .../internal/raw_hash_set_allocator_test.cc        |   2 +
 absl/container/internal/raw_hash_set_test.cc       |   2 +
 absl/container/internal/test_instance_tracker.cc   |   2 +
 absl/container/internal/test_instance_tracker.h    |   2 +
 absl/container/internal/tracked.h                  |   5 +
 .../internal/unordered_map_constructor_test.h      |   2 +
 .../container/internal/unordered_map_lookup_test.h |   2 +
 .../internal/unordered_map_members_test.h          |   2 +
 .../internal/unordered_map_modifiers_test.h        |   2 +
 absl/container/internal/unordered_map_test.cc      |   2 +
 .../internal/unordered_set_constructor_test.h      |   2 +
 .../container/internal/unordered_set_lookup_test.h |   2 +
 .../internal/unordered_set_members_test.h          |   2 +
 .../internal/unordered_set_modifiers_test.h        |   2 +
 absl/container/internal/unordered_set_test.cc      |   2 +
 absl/container/node_hash_map.h                     |   2 +
 absl/container/node_hash_map_test.cc               |   2 +
 absl/container/node_hash_set.h                     |   2 +
 absl/container/node_hash_set_test.cc               |   2 +
 absl/debugging/BUILD.bazel                         |  18 +++-
 absl/debugging/CMakeLists.txt                      |   6 ++
 absl/debugging/failure_signal_handler.cc           |   2 +
 absl/debugging/failure_signal_handler.h            |   4 +
 absl/debugging/internal/address_is_readable.cc     |   4 +
 absl/debugging/internal/address_is_readable.h      |   4 +
 absl/debugging/internal/demangle.cc                |   2 +
 absl/debugging/internal/demangle.h                 |   4 +
 absl/debugging/internal/demangle_test.cc           |   2 +
 absl/debugging/internal/elf_mem_image.cc           |   2 +
 absl/debugging/internal/elf_mem_image.h            |   4 +
 absl/debugging/internal/examine_stack.cc           |   2 +
 absl/debugging/internal/examine_stack.h            |   4 +
 absl/debugging/internal/stack_consumption.cc       |   2 +
 absl/debugging/internal/stack_consumption.h        |   4 +
 absl/debugging/internal/stack_consumption_test.cc  |   2 +
 absl/debugging/internal/stacktrace_aarch64-inl.inc |   2 +
 absl/debugging/internal/stacktrace_arm-inl.inc     |   2 +
 absl/debugging/internal/stacktrace_generic-inl.inc |   2 +
 absl/debugging/internal/stacktrace_powerpc-inl.inc |   2 +
 .../internal/stacktrace_unimplemented-inl.inc      |   2 +
 absl/debugging/internal/stacktrace_win32-inl.inc   |   2 +
 absl/debugging/internal/stacktrace_x86-inl.inc     |   2 +
 absl/debugging/internal/symbolize.h                |   6 ++
 absl/debugging/internal/vdso_support.cc            |   2 +
 absl/debugging/internal/vdso_support.h             |   2 +
 absl/debugging/leak_check.cc                       |   4 +
 absl/debugging/leak_check.h                        |   4 +
 absl/debugging/stacktrace.cc                       |   2 +
 absl/debugging/stacktrace.h                        |   4 +
 absl/debugging/symbolize.h                         |   2 +
 absl/debugging/symbolize_elf.inc                   |   2 +
 absl/debugging/symbolize_unimplemented.inc         |   2 +
 absl/debugging/symbolize_win32.inc                 |   2 +
 absl/flags/declare.h                               |   2 +
 absl/flags/flag.cc                                 |   2 +
 absl/flags/flag.h                                  |   2 +
 absl/flags/flag_test_defs.cc                       |   2 +
 absl/flags/internal/commandlineflag.cc             |   2 +
 absl/flags/internal/commandlineflag.h              |   4 +-
 absl/flags/internal/flag.cc                        | 113 ++++++++++++++-------
 absl/flags/internal/flag.h                         |  54 +++++-----
 absl/flags/internal/parse.h                        |   2 +
 absl/flags/internal/path_util.h                    |   2 +
 absl/flags/internal/program_name.cc                |   2 +
 absl/flags/internal/program_name.h                 |   2 +
 absl/flags/internal/registry.cc                    |   4 +-
 absl/flags/internal/registry.h                     |   2 +
 absl/flags/internal/type_erased.cc                 |   2 +
 absl/flags/internal/type_erased.h                  |   2 +
 absl/flags/internal/usage.cc                       |   2 +
 absl/flags/internal/usage.h                        |   2 +
 absl/flags/marshalling.cc                          |   2 +
 absl/flags/marshalling.h                           |   2 +
 absl/flags/parse.cc                                |   4 +
 absl/flags/parse.h                                 |   2 +
 absl/flags/usage.cc                                |   2 +
 absl/flags/usage.h                                 |   2 +
 absl/flags/usage_config.cc                         |   2 +
 absl/flags/usage_config.h                          |   2 +
 absl/functional/function_ref.h                     |   2 +
 absl/functional/function_ref_benchmark.cc          |   2 +
 absl/functional/function_ref_test.cc               |   2 +
 absl/functional/internal/function_ref.h            |   2 +
 absl/hash/hash.h                                   |   2 +
 absl/hash/hash_test.cc                             |   2 +
 absl/hash/hash_testing.h                           |   2 +
 absl/hash/internal/city.cc                         |   2 +
 absl/hash/internal/city.h                          |   5 +
 absl/hash/internal/city_test.cc                    |   2 +
 absl/hash/internal/hash.cc                         |   2 +
 absl/hash/internal/hash.h                          |   2 +
 absl/hash/internal/spy_hash_state.h                |   2 +
 absl/memory/memory.h                               |   2 +
 absl/memory/memory_exception_safety_test.cc        |   2 +
 absl/meta/type_traits.h                            |   2 +
 absl/numeric/int128.cc                             |   2 +
 absl/numeric/int128.h                              |   6 ++
 absl/random/CMakeLists.txt                         |  14 +++
 absl/random/bernoulli_distribution.h               |   2 +
 absl/random/beta_distribution.h                    |   2 +
 absl/random/bit_gen_ref.h                          |   2 +
 absl/random/bit_gen_ref_test.cc                    |   2 +
 absl/random/discrete_distribution.cc               |   2 +
 absl/random/discrete_distribution.h                |   2 +
 absl/random/distribution_format_traits.h           |   2 +
 absl/random/distributions.h                        |   2 +
 absl/random/exponential_distribution.h             |   2 +
 absl/random/gaussian_distribution.cc               |   2 +
 absl/random/gaussian_distribution.h                |   2 +
 absl/random/internal/BUILD.bazel                   |   9 ++
 absl/random/internal/chi_square.cc                 |   2 +
 absl/random/internal/chi_square.h                  |   4 +
 absl/random/internal/distribution_caller.h         |   4 +
 absl/random/internal/distribution_test_util.cc     |   2 +
 absl/random/internal/distribution_test_util.h      |   2 +
 absl/random/internal/distributions.h               |   2 +
 absl/random/internal/explicit_seed_seq.h           |   4 +
 absl/random/internal/fast_uniform_bits.h           |   4 +
 absl/random/internal/fast_uniform_bits_test.cc     |   2 +
 absl/random/internal/fastmath.h                    |   2 +
 .../internal/gaussian_distribution_gentables.cc    |   2 +
 absl/random/internal/generate_real.h               |   2 +
 absl/random/internal/iostream_state_saver.h        |   2 +
 absl/random/internal/mock_overload_set.h           |   2 +
 absl/random/internal/mocking_bit_gen_base.h        |   2 +
 absl/random/internal/nanobenchmark.cc              |   2 +
 absl/random/internal/nanobenchmark.h               |   4 +
 absl/random/internal/nanobenchmark_test.cc         |   2 +
 absl/random/internal/nonsecure_base.h              |   2 +
 absl/random/internal/pcg_engine.h                  |   2 +
 absl/random/internal/pool_urbg.cc                  |   2 +
 absl/random/internal/pool_urbg.h                   |   2 +
 absl/random/internal/randen.cc                     |   2 +
 absl/random/internal/randen.h                      |   2 +
 absl/random/internal/randen_detect.cc              |   2 +
 absl/random/internal/randen_detect.h               |   4 +
 absl/random/internal/randen_engine.h               |   2 +
 absl/random/internal/randen_hwaes.cc               |   4 +
 absl/random/internal/randen_hwaes.h                |   4 +
 absl/random/internal/randen_slow.cc                |   2 +
 absl/random/internal/randen_slow.h                 |   4 +
 absl/random/internal/randen_traits.h               |   4 +
 absl/random/internal/salted_seed_seq.h             |   2 +
 absl/random/internal/seed_material.cc              |   2 +
 absl/random/internal/seed_material.h               |   2 +
 absl/random/internal/sequence_urbg.h               |   4 +
 absl/random/internal/traits.h                      |   2 +
 absl/random/internal/uniform_helper.h              |   2 +
 absl/random/internal/wide_multiply.h               |   2 +
 absl/random/log_uniform_int_distribution.h         |   2 +
 absl/random/mock_distributions.h                   |   2 +
 absl/random/mocking_bit_gen.cc                     |   2 +
 absl/random/mocking_bit_gen.h                      |   2 +
 absl/random/poisson_distribution.h                 |   2 +
 absl/random/random.h                               |   2 +
 absl/random/seed_gen_exception.cc                  |   2 +
 absl/random/seed_gen_exception.h                   |   4 +
 absl/random/seed_sequences.cc                      |   2 +
 absl/random/seed_sequences.h                       |   2 +
 absl/random/uniform_int_distribution.h             |   2 +
 absl/random/uniform_real_distribution.h            |   2 +
 absl/random/zipf_distribution.h                    |   2 +
 absl/strings/BUILD.bazel                           |   5 +
 absl/strings/CMakeLists.txt                        |   6 ++
 absl/strings/ascii.cc                              |   2 +
 absl/strings/ascii.h                               |   2 +
 absl/strings/charconv.cc                           |   2 +
 absl/strings/charconv.h                            |   4 +
 absl/strings/escaping.cc                           |   2 +
 absl/strings/escaping.h                            |   2 +
 absl/strings/internal/char_map.h                   |   2 +
 absl/strings/internal/charconv_bigint.cc           |   2 +
 absl/strings/internal/charconv_bigint.h            |   2 +
 absl/strings/internal/charconv_bigint_test.cc      |   2 +
 absl/strings/internal/charconv_parse.cc            |   2 +
 absl/strings/internal/charconv_parse.h             |   3 +
 absl/strings/internal/escaping_test_common.h       |   2 +
 absl/strings/internal/memutil.cc                   |   2 +
 absl/strings/internal/memutil.h                    |   2 +
 absl/strings/internal/numbers_test_common.h        |   4 +
 absl/strings/internal/ostringstream.cc             |   2 +
 absl/strings/internal/ostringstream.h              |   2 +
 absl/strings/internal/pow10_helper.cc              |   2 +
 absl/strings/internal/pow10_helper.h               |   4 +
 absl/strings/internal/pow10_helper_test.cc         |   2 +
 absl/strings/internal/resize_uninitialized.h       |   2 +
 absl/strings/internal/stl_type_traits.h            |   2 +
 absl/strings/internal/str_format/arg.cc            |   2 +
 absl/strings/internal/str_format/arg.h             |   2 +
 absl/strings/internal/str_format/arg_test.cc       |   2 +
 absl/strings/internal/str_format/bind.cc           |   2 +
 absl/strings/internal/str_format/bind.h            |   2 +
 absl/strings/internal/str_format/bind_test.cc      |   2 +
 absl/strings/internal/str_format/checker.h         |   2 +
 absl/strings/internal/str_format/checker_test.cc   |   2 +
 absl/strings/internal/str_format/convert_test.cc   |   2 +
 absl/strings/internal/str_format/extension.cc      |   2 +
 absl/strings/internal/str_format/extension.h       |   2 +
 .../internal/str_format/float_conversion.cc        |   2 +
 .../strings/internal/str_format/float_conversion.h |   2 +
 absl/strings/internal/str_format/output.cc         |   2 +
 absl/strings/internal/str_format/output.h          |   2 +
 absl/strings/internal/str_format/output_test.cc    |   2 +
 absl/strings/internal/str_format/parser.cc         |   2 +
 absl/strings/internal/str_format/parser.h          |   2 +
 absl/strings/internal/str_format/parser_test.cc    |   2 +
 absl/strings/internal/str_join_internal.h          |   2 +
 absl/strings/internal/str_split_internal.h         |   2 +
 absl/strings/internal/utf8.cc                      |   2 +
 absl/strings/internal/utf8.h                       |   4 +
 absl/strings/match.cc                              |   2 +
 absl/strings/match.h                               |   4 +-
 absl/strings/numbers.cc                            |   2 +
 absl/strings/numbers.h                             |   4 +
 absl/strings/str_cat.cc                            |   2 +
 absl/strings/str_cat.h                             |   2 +
 absl/strings/str_format.h                          |   2 +
 absl/strings/str_format_test.cc                    |   2 +
 absl/strings/str_join.h                            |   2 +
 absl/strings/str_replace.cc                        |   2 +
 absl/strings/str_replace.h                         |   2 +
 absl/strings/str_split.cc                          |   2 +
 absl/strings/str_split.h                           |   2 +
 absl/strings/string_view.cc                        |   2 +
 absl/strings/string_view.h                         |  20 ++--
 absl/strings/strip.h                               |   2 +
 absl/strings/substitute.cc                         |   2 +
 absl/strings/substitute.h                          |   2 +
 absl/synchronization/BUILD.bazel                   |   1 +
 absl/synchronization/CMakeLists.txt                |   1 +
 absl/synchronization/barrier.cc                    |   2 +
 absl/synchronization/barrier.h                     |   2 +
 absl/synchronization/blocking_counter.cc           |   2 +
 absl/synchronization/blocking_counter.h            |   2 +
 absl/synchronization/blocking_counter_test.cc      |   2 +
 .../internal/create_thread_identity.cc             |   2 +
 .../internal/create_thread_identity.h              |   2 +
 absl/synchronization/internal/graphcycles.cc       |   2 +
 absl/synchronization/internal/graphcycles.h        |   4 +
 absl/synchronization/internal/graphcycles_test.cc  |   2 +
 absl/synchronization/internal/kernel_timeout.h     |   2 +
 absl/synchronization/internal/mutex_nonprod.cc     |   2 +
 absl/synchronization/internal/mutex_nonprod.inc    |   2 +
 absl/synchronization/internal/per_thread_sem.cc    |   2 +
 absl/synchronization/internal/per_thread_sem.h     |   2 +
 .../internal/per_thread_sem_test.cc                |   2 +
 absl/synchronization/internal/thread_pool.h        |   2 +
 absl/synchronization/internal/waiter.cc            |   2 +
 absl/synchronization/internal/waiter.h             |   2 +
 absl/synchronization/mutex.cc                      |   4 +-
 absl/synchronization/mutex.h                       |   4 +-
 absl/synchronization/notification.cc               |   2 +
 absl/synchronization/notification.h                |   2 +
 absl/synchronization/notification_test.cc          |   2 +
 absl/time/civil_time.cc                            |   2 +
 absl/time/civil_time.h                             |   2 +
 absl/time/clock.cc                                 |   8 ++
 absl/time/clock.h                                  |   2 +
 absl/time/duration.cc                              |   2 +
 absl/time/duration_test.cc                         |   5 -
 absl/time/format.cc                                |   2 +
 absl/time/internal/get_current_time_chrono.inc     |   2 +
 absl/time/internal/get_current_time_posix.inc      |   2 +
 absl/time/internal/test_util.cc                    |   4 +
 absl/time/internal/test_util.h                     |   2 +
 absl/time/time.cc                                  |   2 +
 absl/time/time.h                                   |   2 +
 absl/types/any.h                                   |   4 +
 absl/types/bad_any_cast.cc                         |   2 +
 absl/types/bad_any_cast.h                          |   4 +
 absl/types/bad_optional_access.cc                  |   2 +
 absl/types/bad_optional_access.h                   |   4 +
 absl/types/bad_variant_access.cc                   |   2 +
 absl/types/bad_variant_access.h                    |   4 +
 absl/types/compare.h                               |   2 +
 absl/types/compare_test.cc                         |   2 +
 absl/types/internal/conformance_aliases.h          |   2 +
 absl/types/internal/conformance_archetype.h        |   2 +
 absl/types/internal/conformance_profile.h          |   2 +
 absl/types/internal/optional.h                     |   2 +
 absl/types/internal/span.h                         |   2 +
 absl/types/internal/variant.h                      |   2 +
 absl/types/optional.h                              |   4 +
 absl/types/optional_exception_safety_test.cc       |   2 +
 absl/types/span.h                                  |   2 +
 absl/types/variant.h                               |   6 ++
 absl/types/variant_benchmark.cc                    |   2 +
 absl/types/variant_exception_safety_test.cc        |   2 +
 absl/types/variant_test.cc                         |   2 +
 absl/utility/utility.h                             |   2 +
 339 files changed, 949 insertions(+), 83 deletions(-)

(limited to 'absl/debugging/leak_check.h')

diff --git a/absl/algorithm/BUILD.bazel b/absl/algorithm/BUILD.bazel
index 2ee8c09e..6a96420b 100644
--- a/absl/algorithm/BUILD.bazel
+++ b/absl/algorithm/BUILD.bazel
@@ -31,6 +31,7 @@ cc_library(
     hdrs = ["algorithm.h"],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = ["//absl/base:config"],
 )
 
 cc_test(
diff --git a/absl/algorithm/CMakeLists.txt b/absl/algorithm/CMakeLists.txt
index 9fbe36f6..56cd0fb8 100644
--- a/absl/algorithm/CMakeLists.txt
+++ b/absl/algorithm/CMakeLists.txt
@@ -21,6 +21,8 @@ absl_cc_library(
     "algorithm.h"
   COPTS
     ${ABSL_DEFAULT_COPTS}
+  DEPS
+    absl::config
   PUBLIC
 )
 
diff --git a/absl/algorithm/algorithm.h b/absl/algorithm/algorithm.h
index 771228a0..e9b47338 100644
--- a/absl/algorithm/algorithm.h
+++ b/absl/algorithm/algorithm.h
@@ -26,7 +26,10 @@
 #include <iterator>
 #include <type_traits>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace algorithm_internal {
 
@@ -150,6 +153,7 @@ ForwardIterator rotate(ForwardIterator first, ForwardIterator middle,
                    ForwardIterator>());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_ALGORITHM_ALGORITHM_H_
diff --git a/absl/algorithm/container.h b/absl/algorithm/container.h
index 5dae9fd6..d72532de 100644
--- a/absl/algorithm/container.h
+++ b/absl/algorithm/container.h
@@ -55,6 +55,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_algorithm_internal {
 
 // NOTE: it is important to defer to ADL lookup for building with C++ modules,
@@ -1720,6 +1721,7 @@ OutputIt c_partial_sum(const InputSequence& input, OutputIt output_first,
                           output_first, std::forward<BinaryOp>(op));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_ALGORITHM_CONTAINER_H_
diff --git a/absl/base/internal/raw_logging.h b/absl/base/internal/raw_logging.h
index 12145c48..cff45058 100644
--- a/absl/base/internal/raw_logging.h
+++ b/absl/base/internal/raw_logging.h
@@ -154,7 +154,7 @@ using LogPrefixHook = bool (*)(absl::LogSeverity severity, const char* file,
 //
 // 'file' and 'line' are the file and line number where the ABSL_RAW_LOG macro
 // was located.
-// The null-terminated logged message lives in the buffer between 'buf_start'
+// The NUL-terminated logged message lives in the buffer between 'buf_start'
 // and 'buf_end'.  'prefix_end' points to the first non-prefix character of the
 // buffer (as written by the LogPrefixHook.)
 using AbortHook = void (*)(const char* file, int line, const char* buf_start,
diff --git a/absl/base/internal/thread_identity.h b/absl/base/internal/thread_identity.h
index a1aa45ff..5dfd0715 100644
--- a/absl/base/internal/thread_identity.h
+++ b/absl/base/internal/thread_identity.h
@@ -209,7 +209,7 @@ void ClearCurrentThreadIdentity();
 #error ABSL_THREAD_IDENTITY_MODE cannot be direcly set
 #elif defined(ABSL_FORCE_THREAD_IDENTITY_MODE)
 #define ABSL_THREAD_IDENTITY_MODE ABSL_FORCE_THREAD_IDENTITY_MODE
-#elif defined(_WIN32)
+#elif defined(_WIN32) && !defined(__MINGW32__)
 #define ABSL_THREAD_IDENTITY_MODE ABSL_THREAD_IDENTITY_MODE_USE_CPP11
 #elif ABSL_PER_THREAD_TLS && defined(__GOOGLE_GRTE_VERSION__) && \
     (__GOOGLE_GRTE_VERSION__ >= 20140228L)
diff --git a/absl/container/BUILD.bazel b/absl/container/BUILD.bazel
index e60979b2..1f7abe07 100644
--- a/absl/container/BUILD.bazel
+++ b/absl/container/BUILD.bazel
@@ -141,6 +141,7 @@ cc_library(
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
     visibility = ["//visibility:private"],
+    deps = ["//absl/base:config"],
 )
 
 cc_test(
@@ -478,6 +479,9 @@ cc_library(
     hdrs = ["internal/hashtable_debug_hooks.h"],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = [
+        "//absl/base:config",
+    ],
 )
 
 cc_library(
@@ -521,6 +525,7 @@ cc_library(
     hdrs = ["internal/node_hash_policy.h"],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = ["//absl/base:config"],
 )
 
 cc_test(
@@ -662,6 +667,9 @@ cc_library(
     hdrs = ["internal/tracked.h"],
     copts = ABSL_TEST_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = [
+        "//absl/base:config",
+    ],
 )
 
 cc_library(
diff --git a/absl/container/CMakeLists.txt b/absl/container/CMakeLists.txt
index aa33659b..a931f334 100644
--- a/absl/container/CMakeLists.txt
+++ b/absl/container/CMakeLists.txt
@@ -204,6 +204,8 @@ absl_cc_library(
     "internal/counting_allocator.h"
   COPTS
     ${ABSL_DEFAULT_COPTS}
+  DEPS
+    absl::config
 )
 
 absl_cc_test(
@@ -574,6 +576,8 @@ absl_cc_library(
     "internal/hashtable_debug_hooks.h"
   COPTS
     ${ABSL_DEFAULT_COPTS}
+  DEPS
+    absl::config
   PUBLIC
 )
 
@@ -593,6 +597,8 @@ absl_cc_library(
     "internal/node_hash_policy.h"
   COPTS
     ${ABSL_DEFAULT_COPTS}
+  DEPS
+    absl::config
   PUBLIC
 )
 
@@ -735,6 +741,8 @@ absl_cc_library(
     "internal/tracked.h"
   COPTS
     ${ABSL_TEST_COPTS}
+  DEPS
+    absl::config
   TESTONLY
 )
 
diff --git a/absl/container/btree_map.h b/absl/container/btree_map.h
index 9f35f639..470e3197 100644
--- a/absl/container/btree_map.h
+++ b/absl/container/btree_map.h
@@ -51,6 +51,7 @@
 #include "absl/container/internal/btree_container.h"  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::btree_map<>
 //
@@ -700,6 +701,7 @@ void swap(btree_multimap<K, V, C, A> &x, btree_multimap<K, V, C, A> &y) {
   return x.swap(y);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_BTREE_MAP_H_
diff --git a/absl/container/btree_set.h b/absl/container/btree_set.h
index 6e47b4aa..2a4d0ace 100644
--- a/absl/container/btree_set.h
+++ b/absl/container/btree_set.h
@@ -51,6 +51,7 @@
 #include "absl/container/internal/btree_container.h"  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::btree_set<>
 //
@@ -648,6 +649,7 @@ void swap(btree_multiset<K, C, A> &x, btree_multiset<K, C, A> &y) {
   return x.swap(y);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_BTREE_SET_H_
diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index ea73f032..f8aadd62 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -42,6 +42,7 @@
 ABSL_FLAG(int, test_values, 10000, "The number of values to use for tests");
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -2304,4 +2305,5 @@ TEST(Btree, EmptyTree) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/btree_test.h b/absl/container/btree_test.h
index 5ecf43ce..218ba41d 100644
--- a/absl/container/btree_test.h
+++ b/absl/container/btree_test.h
@@ -28,6 +28,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // Like remove_const but propagates the removal through std::pair.
@@ -148,6 +149,7 @@ std::vector<V> GenerateValuesWithSeed(int n, int maxval, int seed) {
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_BTREE_TEST_H_
diff --git a/absl/container/fixed_array.h b/absl/container/fixed_array.h
index 70e94ad5..a9ce99ba 100644
--- a/absl/container/fixed_array.h
+++ b/absl/container/fixed_array.h
@@ -50,6 +50,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 constexpr static auto kFixedArrayUseDefault = static_cast<size_t>(-1);
 
@@ -508,6 +509,7 @@ void FixedArray<T, N, A>::NonEmptyInlinedStorage::AnnotateDestruct(
 #endif                   // ADDRESS_SANITIZER
   static_cast<void>(n);  // Mark used when not in asan mode
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_FIXED_ARRAY_H_
diff --git a/absl/container/fixed_array_exception_safety_test.cc b/absl/container/fixed_array_exception_safety_test.cc
index 5ebeac05..a5bb009d 100644
--- a/absl/container/fixed_array_exception_safety_test.cc
+++ b/absl/container/fixed_array_exception_safety_test.cc
@@ -23,6 +23,7 @@
 #include "absl/base/internal/exception_safety_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -195,6 +196,7 @@ TEST(FixedArrayExceptionSafety, FillWithAlloc) {
 
 }  // namespace
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_EXCEPTIONS
diff --git a/absl/container/flat_hash_map.h b/absl/container/flat_hash_map.h
index 283f2439..fb570cd4 100644
--- a/absl/container/flat_hash_map.h
+++ b/absl/container/flat_hash_map.h
@@ -42,6 +42,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 template <class K, class V>
 struct FlatHashMapPolicy;
@@ -584,6 +585,7 @@ struct IsUnorderedContainer<
 
 }  // namespace container_algorithm_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_FLAT_HASH_MAP_H_
diff --git a/absl/container/flat_hash_map_test.cc b/absl/container/flat_hash_map_test.cc
index 02d1f879..dae8e003 100644
--- a/absl/container/flat_hash_map_test.cc
+++ b/absl/container/flat_hash_map_test.cc
@@ -24,6 +24,7 @@
 #include "absl/types/any.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 using ::absl::container_internal::hash_internal::Enum;
@@ -251,4 +252,5 @@ TEST(FlatHashMap, Any) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/flat_hash_set.h b/absl/container/flat_hash_set.h
index 2a51c341..930107ea 100644
--- a/absl/container/flat_hash_set.h
+++ b/absl/container/flat_hash_set.h
@@ -40,6 +40,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 template <typename T>
 struct FlatHashSetPolicy;
@@ -488,6 +489,7 @@ struct IsUnorderedContainer<absl::flat_hash_set<Key, Hash, KeyEqual, Allocator>>
 
 }  // namespace container_algorithm_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_FLAT_HASH_SET_H_
diff --git a/absl/container/flat_hash_set_test.cc b/absl/container/flat_hash_set_test.cc
index b55be59b..6eacb1bb 100644
--- a/absl/container/flat_hash_set_test.cc
+++ b/absl/container/flat_hash_set_test.cc
@@ -25,6 +25,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -125,4 +126,5 @@ TEST(FlatHashSet, MergeExtractInsert) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/inlined_vector.h b/absl/container/inlined_vector.h
index d5c67db5..2388d471 100644
--- a/absl/container/inlined_vector.h
+++ b/absl/container/inlined_vector.h
@@ -54,6 +54,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 // -----------------------------------------------------------------------------
 // InlinedVector
 // -----------------------------------------------------------------------------
@@ -841,6 +842,7 @@ H AbslHashValue(H h, const absl::InlinedVector<T, N, A>& a) {
   return H::combine(H::combine_contiguous(std::move(h), a.data(), size), size);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INLINED_VECTOR_H_
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h
index 40217dd5..aef861dc 100644
--- a/absl/container/internal/btree.h
+++ b/absl/container/internal/btree.h
@@ -70,6 +70,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // A helper class that indicates if the Compare parameter is a key-compare-to
@@ -2606,6 +2607,7 @@ int btree<P>::internal_verify(
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_BTREE_H_
diff --git a/absl/container/internal/btree_container.h b/absl/container/internal/btree_container.h
index 774412d9..04795c2e 100644
--- a/absl/container/internal/btree_container.h
+++ b/absl/container/internal/btree_container.h
@@ -26,6 +26,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // A common base class for btree_set, btree_map, btree_multiset, and
@@ -602,6 +603,7 @@ class btree_multimap_container : public btree_multiset_container<Tree> {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_BTREE_CONTAINER_H_
diff --git a/absl/container/internal/common.h b/absl/container/internal/common.h
index cc7633dc..853a5b21 100644
--- a/absl/container/internal/common.h
+++ b/absl/container/internal/common.h
@@ -22,6 +22,7 @@
 #include "absl/types/optional.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class, class = void>
@@ -196,6 +197,7 @@ struct InsertReturnType {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_CONTAINER_H_
diff --git a/absl/container/internal/compressed_tuple.h b/absl/container/internal/compressed_tuple.h
index 7d08e370..4bfe92fd 100644
--- a/absl/container/internal/compressed_tuple.h
+++ b/absl/container/internal/compressed_tuple.h
@@ -48,6 +48,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <typename... Ts>
@@ -256,6 +257,7 @@ template <>
 class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple<> {};
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC
diff --git a/absl/container/internal/compressed_tuple_test.cc b/absl/container/internal/compressed_tuple_test.cc
index 19af8f10..76bc9213 100644
--- a/absl/container/internal/compressed_tuple_test.cc
+++ b/absl/container/internal/compressed_tuple_test.cc
@@ -48,6 +48,7 @@ struct TwoValues {
 
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -408,4 +409,5 @@ TEST(CompressedTupleTest, EmptyFinalClass) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/container_memory.h b/absl/container/internal/container_memory.h
index e5bb9773..d24b0f84 100644
--- a/absl/container/internal/container_memory.h
+++ b/absl/container/internal/container_memory.h
@@ -34,6 +34,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // Allocates at least n bytes aligned to the specified alignment.
@@ -433,6 +434,7 @@ struct map_slot_policy {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_CONTAINER_MEMORY_H_
diff --git a/absl/container/internal/container_memory_test.cc b/absl/container/internal/container_memory_test.cc
index d6b0495f..7942c7be 100644
--- a/absl/container/internal/container_memory_test.cc
+++ b/absl/container/internal/container_memory_test.cc
@@ -23,6 +23,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -185,4 +186,5 @@ TEST(DecomposePair, NotDecomposable) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/counting_allocator.h b/absl/container/internal/counting_allocator.h
index 4e717bef..9efdc662 100644
--- a/absl/container/internal/counting_allocator.h
+++ b/absl/container/internal/counting_allocator.h
@@ -19,7 +19,10 @@
 #include <cstdint>
 #include <memory>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // This is a stateful allocator, but the state lives outside of the
@@ -74,6 +77,7 @@ class CountingAllocator : public std::allocator<T> {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_COUNTING_ALLOCATOR_H_
diff --git a/absl/container/internal/hash_function_defaults.h b/absl/container/internal/hash_function_defaults.h
index cb8f03c8..401ddf4d 100644
--- a/absl/container/internal/hash_function_defaults.h
+++ b/absl/container/internal/hash_function_defaults.h
@@ -56,6 +56,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // The hash of an object of type T is computed by using absl::Hash.
@@ -139,6 +140,7 @@ template <class T>
 using hash_default_eq = typename container_internal::HashEq<T>::Eq;
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASH_FUNCTION_DEFAULTS_H_
diff --git a/absl/container/internal/hash_function_defaults_test.cc b/absl/container/internal/hash_function_defaults_test.cc
index 82708dbe..2eefc7e0 100644
--- a/absl/container/internal/hash_function_defaults_test.cc
+++ b/absl/container/internal/hash_function_defaults_test.cc
@@ -22,6 +22,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -248,6 +249,7 @@ TYPED_TEST_SUITE(StringLikeTest, StringTypesCartesianProduct);
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 enum Hash : size_t {
@@ -278,6 +280,7 @@ struct hash<Hashable<H>> {
 }  // namespace std
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -292,4 +295,5 @@ TEST(Delegate, HashDispatch) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hash_generator_testing.cc b/absl/container/internal/hash_generator_testing.cc
index 37a23d60..75c4db6c 100644
--- a/absl/container/internal/hash_generator_testing.cc
+++ b/absl/container/internal/hash_generator_testing.cc
@@ -17,6 +17,7 @@
 #include <deque>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace hash_internal {
 namespace {
@@ -69,4 +70,5 @@ absl::string_view Generator<absl::string_view>::operator()() const {
 
 }  // namespace hash_internal
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hash_generator_testing.h b/absl/container/internal/hash_generator_testing.h
index 477215cd..6869fe45 100644
--- a/absl/container/internal/hash_generator_testing.h
+++ b/absl/container/internal/hash_generator_testing.h
@@ -33,6 +33,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace hash_internal {
 namespace generator_internal {
@@ -154,6 +155,7 @@ using GeneratedType = decltype(
 
 }  // namespace hash_internal
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASH_GENERATOR_TESTING_H_
diff --git a/absl/container/internal/hash_policy_testing.h b/absl/container/internal/hash_policy_testing.h
index c57407a0..01c40d2e 100644
--- a/absl/container/internal/hash_policy_testing.h
+++ b/absl/container/internal/hash_policy_testing.h
@@ -30,6 +30,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace hash_testing_internal {
 
@@ -162,6 +163,7 @@ auto keys(const Set& s)
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // ABSL_UNORDERED_SUPPORTS_ALLOC_CTORS is false for glibcxx versions
diff --git a/absl/container/internal/hash_policy_testing_test.cc b/absl/container/internal/hash_policy_testing_test.cc
index 0c95eb5e..f0b20fe3 100644
--- a/absl/container/internal/hash_policy_testing_test.cc
+++ b/absl/container/internal/hash_policy_testing_test.cc
@@ -17,6 +17,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -40,4 +41,5 @@ TEST(_, Hash) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hash_policy_traits.h b/absl/container/internal/hash_policy_traits.h
index fd007de7..3e1209c6 100644
--- a/absl/container/internal/hash_policy_traits.h
+++ b/absl/container/internal/hash_policy_traits.h
@@ -23,6 +23,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // Defines how slots are initialized/destroyed/moved.
@@ -184,6 +185,7 @@ struct hash_policy_traits {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASH_POLICY_TRAITS_H_
diff --git a/absl/container/internal/hash_policy_traits_test.cc b/absl/container/internal/hash_policy_traits_test.cc
index e643d189..6ef8b9e0 100644
--- a/absl/container/internal/hash_policy_traits_test.cc
+++ b/absl/container/internal/hash_policy_traits_test.cc
@@ -22,6 +22,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -139,4 +140,5 @@ TEST_F(Test, with_transfer) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hashtable_debug.h b/absl/container/internal/hashtable_debug.h
index 71930004..19d52121 100644
--- a/absl/container/internal/hashtable_debug.h
+++ b/absl/container/internal/hashtable_debug.h
@@ -38,6 +38,7 @@
 #include "absl/container/internal/hashtable_debug_hooks.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // Returns the number of probes required to lookup `key`.  Returns 0 for a
@@ -103,6 +104,7 @@ size_t LowerBoundAllocatedByteSize(size_t num_elements) {
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_H_
diff --git a/absl/container/internal/hashtable_debug_hooks.h b/absl/container/internal/hashtable_debug_hooks.h
index 371ce81f..3e9ea595 100644
--- a/absl/container/internal/hashtable_debug_hooks.h
+++ b/absl/container/internal/hashtable_debug_hooks.h
@@ -23,7 +23,10 @@
 #include <type_traits>
 #include <vector>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace hashtable_debug_internal {
 
@@ -76,6 +79,7 @@ struct HashtableDebugAccess {
 
 }  // namespace hashtable_debug_internal
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASHTABLE_DEBUG_HOOKS_H_
diff --git a/absl/container/internal/hashtablez_sampler.cc b/absl/container/internal/hashtablez_sampler.cc
index 6deeca44..e15f4444 100644
--- a/absl/container/internal/hashtablez_sampler.cc
+++ b/absl/container/internal/hashtablez_sampler.cc
@@ -28,6 +28,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 constexpr int HashtablezInfo::kMaxStackDepth;
 
@@ -265,4 +266,5 @@ void SetHashtablezMaxSamples(int32_t max) {
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hashtablez_sampler.h b/absl/container/internal/hashtablez_sampler.h
index c694df05..c4f9629f 100644
--- a/absl/container/internal/hashtablez_sampler.h
+++ b/absl/container/internal/hashtablez_sampler.h
@@ -51,6 +51,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // Stores information about a sampled hashtable.  All mutations to this *must*
@@ -281,6 +282,7 @@ void SetHashtablezMaxSamples(int32_t max);
 extern "C" bool AbslContainerInternalSampleEverything();
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_HASHTABLEZ_SAMPLER_H_
diff --git a/absl/container/internal/hashtablez_sampler_force_weak_definition.cc b/absl/container/internal/hashtablez_sampler_force_weak_definition.cc
index 984dce5d..78b9d362 100644
--- a/absl/container/internal/hashtablez_sampler_force_weak_definition.cc
+++ b/absl/container/internal/hashtablez_sampler_force_weak_definition.cc
@@ -17,6 +17,7 @@
 #include "absl/base/attributes.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // See hashtablez_sampler.h for details.
@@ -25,4 +26,5 @@ extern "C" ABSL_ATTRIBUTE_WEAK bool AbslContainerInternalSampleEverything() {
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/hashtablez_sampler_test.cc b/absl/container/internal/hashtablez_sampler_test.cc
index af4b5ee1..102b2375 100644
--- a/absl/container/internal/hashtablez_sampler_test.cc
+++ b/absl/container/internal/hashtablez_sampler_test.cc
@@ -36,6 +36,7 @@ constexpr int kProbeLength = 8;
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 class HashtablezInfoHandlePeer {
  public:
@@ -354,4 +355,5 @@ TEST(HashtablezSamplerTest, Callback) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/inlined_vector.h b/absl/container/internal/inlined_vector.h
index 84aa785a..4d80b727 100644
--- a/absl/container/internal/inlined_vector.h
+++ b/absl/container/internal/inlined_vector.h
@@ -30,6 +30,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace inlined_vector_internal {
 
 template <typename Iterator>
@@ -885,6 +886,7 @@ auto Storage<T, N, A>::Swap(Storage* other_storage_ptr) -> void {
 }
 
 }  // namespace inlined_vector_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_INLINED_VECTOR_INTERNAL_H_
diff --git a/absl/container/internal/layout.h b/absl/container/internal/layout.h
index bbdde507..69cc85dd 100644
--- a/absl/container/internal/layout.h
+++ b/absl/container/internal/layout.h
@@ -188,6 +188,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // A type wrapper that instructs `Layout` to use the specific alignment for the
@@ -734,6 +735,7 @@ class Layout : public internal_layout::LayoutType<sizeof...(Ts), Ts...> {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_LAYOUT_H_
diff --git a/absl/container/internal/layout_test.cc b/absl/container/internal/layout_test.cc
index 33b72bd3..8f3628a1 100644
--- a/absl/container/internal/layout_test.cc
+++ b/absl/container/internal/layout_test.cc
@@ -28,6 +28,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -1562,4 +1563,5 @@ TEST(CompactString, Works) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/node_hash_policy.h b/absl/container/internal/node_hash_policy.h
index 19b4fc09..4617162f 100644
--- a/absl/container/internal/node_hash_policy.h
+++ b/absl/container/internal/node_hash_policy.h
@@ -39,7 +39,10 @@
 #include <type_traits>
 #include <utility>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class Reference, class Policy>
@@ -83,6 +86,7 @@ struct node_hash_policy {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_NODE_HASH_POLICY_H_
diff --git a/absl/container/internal/node_hash_policy_test.cc b/absl/container/internal/node_hash_policy_test.cc
index f1d3ec30..84aabba9 100644
--- a/absl/container/internal/node_hash_policy_test.cc
+++ b/absl/container/internal/node_hash_policy_test.cc
@@ -21,6 +21,7 @@
 #include "absl/container/internal/hash_policy_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -64,4 +65,5 @@ TEST_F(NodeTest, transfer) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/raw_hash_map.h b/absl/container/internal/raw_hash_map.h
index 7dad120a..0a02757d 100644
--- a/absl/container/internal/raw_hash_map.h
+++ b/absl/container/internal/raw_hash_map.h
@@ -24,6 +24,7 @@
 #include "absl/container/internal/raw_hash_set.h"  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class Policy, class Hash, class Eq, class Alloc>
@@ -190,6 +191,7 @@ class raw_hash_map : public raw_hash_set<Policy, Hash, Eq, Alloc> {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_RAW_HASH_MAP_H_
diff --git a/absl/container/internal/raw_hash_set.cc b/absl/container/internal/raw_hash_set.cc
index ac2d10a7..919ac074 100644
--- a/absl/container/internal/raw_hash_set.cc
+++ b/absl/container/internal/raw_hash_set.cc
@@ -20,6 +20,7 @@
 #include "absl/base/config.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 constexpr size_t Group::kWidth;
@@ -43,4 +44,5 @@ bool ShouldInsertBackwards(size_t hash, ctrl_t* ctrl) {
 }
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
index 469226fe..4103e02a 100644
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -118,6 +118,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <size_t Width>
@@ -1861,6 +1862,7 @@ struct HashtableDebugAccess<Set, absl::void_t<typename Set::raw_hash_set>> {
 
 }  // namespace hashtable_debug_internal
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_RAW_HASH_SET_H_
diff --git a/absl/container/internal/raw_hash_set_allocator_test.cc b/absl/container/internal/raw_hash_set_allocator_test.cc
index a5eff0b3..7ac4b9f7 100644
--- a/absl/container/internal/raw_hash_set_allocator_test.cc
+++ b/absl/container/internal/raw_hash_set_allocator_test.cc
@@ -20,6 +20,7 @@
 #include "absl/container/internal/tracked.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -425,4 +426,5 @@ TEST_F(PropagateOnAll, Swap) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc
index ec8f9231..38e5e0e8 100644
--- a/absl/container/internal/raw_hash_set_test.cc
+++ b/absl/container/internal/raw_hash_set_test.cc
@@ -35,6 +35,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 struct RawHashSetTestOnlyAccess {
@@ -1913,4 +1914,5 @@ TEST(Sanitizer, PoisoningOnErase) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/test_instance_tracker.cc b/absl/container/internal/test_instance_tracker.cc
index 5a66cb4d..f9947f04 100644
--- a/absl/container/internal/test_instance_tracker.cc
+++ b/absl/container/internal/test_instance_tracker.cc
@@ -15,6 +15,7 @@
 #include "absl/container/internal/test_instance_tracker.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace test_internal {
 int BaseCountedInstance::num_instances_ = 0;
 int BaseCountedInstance::num_live_instances_ = 0;
@@ -24,4 +25,5 @@ int BaseCountedInstance::num_swaps_ = 0;
 int BaseCountedInstance::num_comparisons_ = 0;
 
 }  // namespace test_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/test_instance_tracker.h b/absl/container/internal/test_instance_tracker.h
index c4731dbe..5ff6fd71 100644
--- a/absl/container/internal/test_instance_tracker.h
+++ b/absl/container/internal/test_instance_tracker.h
@@ -21,6 +21,7 @@
 #include "absl/types/compare.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace test_internal {
 
 // A type that counts number of occurrences of the type, the live occurrences of
@@ -267,6 +268,7 @@ class MovableOnlyInstance : public BaseCountedInstance {
 };
 
 }  // namespace test_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_TEST_INSTANCE_TRACKER_H_
diff --git a/absl/container/internal/tracked.h b/absl/container/internal/tracked.h
index 75173ab0..29f5829f 100644
--- a/absl/container/internal/tracked.h
+++ b/absl/container/internal/tracked.h
@@ -16,10 +16,14 @@
 #define ABSL_CONTAINER_INTERNAL_TRACKED_H_
 
 #include <stddef.h>
+
 #include <memory>
 #include <utility>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 // A class that tracks its copies and moves so that it can be queried in tests.
@@ -73,6 +77,7 @@ class Tracked {
 };
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_TRACKED_H_
diff --git a/absl/container/internal/unordered_map_constructor_test.h b/absl/container/internal/unordered_map_constructor_test.h
index 68817e4e..76ee95e6 100644
--- a/absl/container/internal/unordered_map_constructor_test.h
+++ b/absl/container/internal/unordered_map_constructor_test.h
@@ -24,6 +24,7 @@
 #include "absl/container/internal/hash_policy_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordMap>
@@ -482,6 +483,7 @@ REGISTER_TYPED_TEST_CASE_P(
     AssignmentFromInitializerListOverwritesExisting, AssignmentOnSelf);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_CONSTRUCTOR_TEST_H_
diff --git a/absl/container/internal/unordered_map_lookup_test.h b/absl/container/internal/unordered_map_lookup_test.h
index ebd3612b..e76421e5 100644
--- a/absl/container/internal/unordered_map_lookup_test.h
+++ b/absl/container/internal/unordered_map_lookup_test.h
@@ -21,6 +21,7 @@
 #include "absl/container/internal/hash_policy_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordMap>
@@ -110,6 +111,7 @@ REGISTER_TYPED_TEST_CASE_P(LookupTest, At, OperatorBracket, Count, Find,
                            EqualRange);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_LOOKUP_TEST_H_
diff --git a/absl/container/internal/unordered_map_members_test.h b/absl/container/internal/unordered_map_members_test.h
index 1bf31ab4..7d48cdb8 100644
--- a/absl/container/internal/unordered_map_members_test.h
+++ b/absl/container/internal/unordered_map_members_test.h
@@ -21,6 +21,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordMap>
@@ -80,6 +81,7 @@ TYPED_TEST_P(MembersTest, BeginEnd) {
 REGISTER_TYPED_TEST_SUITE_P(MembersTest, Typedefs, SimpleFunctions, BeginEnd);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MEMBERS_TEST_H_
diff --git a/absl/container/internal/unordered_map_modifiers_test.h b/absl/container/internal/unordered_map_modifiers_test.h
index f6aff542..b8c513f1 100644
--- a/absl/container/internal/unordered_map_modifiers_test.h
+++ b/absl/container/internal/unordered_map_modifiers_test.h
@@ -23,6 +23,7 @@
 #include "absl/container/internal/hash_policy_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordMap>
@@ -309,6 +310,7 @@ TYPED_TEST_P(UniquePtrModifiersTest, TryEmplace) {
 REGISTER_TYPED_TEST_SUITE_P(UniquePtrModifiersTest, TryEmplace);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_MAP_MODIFIERS_TEST_H_
diff --git a/absl/container/internal/unordered_map_test.cc b/absl/container/internal/unordered_map_test.cc
index 114b342d..9cbf512f 100644
--- a/absl/container/internal/unordered_map_test.cc
+++ b/absl/container/internal/unordered_map_test.cc
@@ -21,6 +21,7 @@
 #include "absl/container/internal/unordered_map_modifiers_test.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -45,4 +46,5 @@ INSTANTIATE_TYPED_TEST_SUITE_P(UnorderedMap, UniquePtrModifiersTest,
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/internal/unordered_set_constructor_test.h b/absl/container/internal/unordered_set_constructor_test.h
index f4844683..41165b05 100644
--- a/absl/container/internal/unordered_set_constructor_test.h
+++ b/absl/container/internal/unordered_set_constructor_test.h
@@ -26,6 +26,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordMap>
@@ -489,6 +490,7 @@ REGISTER_TYPED_TEST_CASE_P(
     AssignmentFromInitializerListOverwritesExisting, AssignmentOnSelf);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_CONSTRUCTOR_TEST_H_
diff --git a/absl/container/internal/unordered_set_lookup_test.h b/absl/container/internal/unordered_set_lookup_test.h
index 05b32b5d..8f2f4b20 100644
--- a/absl/container/internal/unordered_set_lookup_test.h
+++ b/absl/container/internal/unordered_set_lookup_test.h
@@ -21,6 +21,7 @@
 #include "absl/container/internal/hash_policy_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordSet>
@@ -84,6 +85,7 @@ TYPED_TEST_P(LookupTest, EqualRange) {
 REGISTER_TYPED_TEST_CASE_P(LookupTest, Count, Find, EqualRange);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_LOOKUP_TEST_H_
diff --git a/absl/container/internal/unordered_set_members_test.h b/absl/container/internal/unordered_set_members_test.h
index b96c945a..4c5e104a 100644
--- a/absl/container/internal/unordered_set_members_test.h
+++ b/absl/container/internal/unordered_set_members_test.h
@@ -21,6 +21,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordSet>
@@ -79,6 +80,7 @@ TYPED_TEST_P(MembersTest, BeginEnd) {
 REGISTER_TYPED_TEST_SUITE_P(MembersTest, Typedefs, SimpleFunctions, BeginEnd);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MEMBERS_TEST_H_
diff --git a/absl/container/internal/unordered_set_modifiers_test.h b/absl/container/internal/unordered_set_modifiers_test.h
index 79a8d422..26be58d9 100644
--- a/absl/container/internal/unordered_set_modifiers_test.h
+++ b/absl/container/internal/unordered_set_modifiers_test.h
@@ -21,6 +21,7 @@
 #include "absl/container/internal/hash_policy_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 
 template <class UnordSet>
@@ -183,6 +184,7 @@ REGISTER_TYPED_TEST_CASE_P(ModifiersTest, Clear, Insert, InsertHint,
                            EraseKey, Swap);
 
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_INTERNAL_UNORDERED_SET_MODIFIERS_TEST_H_
diff --git a/absl/container/internal/unordered_set_test.cc b/absl/container/internal/unordered_set_test.cc
index 6478fac1..a134b539 100644
--- a/absl/container/internal/unordered_set_test.cc
+++ b/absl/container/internal/unordered_set_test.cc
@@ -20,6 +20,7 @@
 #include "absl/container/internal/unordered_set_modifiers_test.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -36,4 +37,5 @@ INSTANTIATE_TYPED_TEST_SUITE_P(UnorderedSet, ModifiersTest, SetTypes);
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/node_hash_map.h b/absl/container/node_hash_map.h
index a718842b..e8065a98 100644
--- a/absl/container/node_hash_map.h
+++ b/absl/container/node_hash_map.h
@@ -48,6 +48,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 template <class Key, class Value>
 class NodeHashMapPolicy;
@@ -581,6 +582,7 @@ struct IsUnorderedContainer<
 
 }  // namespace container_algorithm_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_NODE_HASH_MAP_H_
diff --git a/absl/container/node_hash_map_test.cc b/absl/container/node_hash_map_test.cc
index 0f2714a7..f923e915 100644
--- a/absl/container/node_hash_map_test.cc
+++ b/absl/container/node_hash_map_test.cc
@@ -21,6 +21,7 @@
 #include "absl/container/internal/unordered_map_modifiers_test.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 
@@ -217,4 +218,5 @@ TEST(NodeHashMap, MergeExtractInsert) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/container/node_hash_set.h b/absl/container/node_hash_set.h
index 0cd1fe57..43ada3f9 100644
--- a/absl/container/node_hash_set.h
+++ b/absl/container/node_hash_set.h
@@ -44,6 +44,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 template <typename T>
 struct NodeHashSetPolicy;
@@ -483,6 +484,7 @@ struct IsUnorderedContainer<absl::node_hash_set<Key, Hash, KeyEqual, Allocator>>
     : std::true_type {};
 
 }  // namespace container_algorithm_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_CONTAINER_NODE_HASH_SET_H_
diff --git a/absl/container/node_hash_set_test.cc b/absl/container/node_hash_set_test.cc
index 0ea76e7c..e1d544ff 100644
--- a/absl/container/node_hash_set_test.cc
+++ b/absl/container/node_hash_set_test.cc
@@ -20,6 +20,7 @@
 #include "absl/container/internal/unordered_set_modifiers_test.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace container_internal {
 namespace {
 using ::absl::container_internal::hash_internal::Enum;
@@ -102,4 +103,5 @@ TEST(NodeHashSet, MergeExtractInsert) {
 
 }  // namespace
 }  // namespace container_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/BUILD.bazel b/absl/debugging/BUILD.bazel
index 2601090b..32cacefd 100644
--- a/absl/debugging/BUILD.bazel
+++ b/absl/debugging/BUILD.bazel
@@ -38,6 +38,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":debugging_internal",
+        "//absl/base:config",
         "//absl/base:core_headers",
     ],
 )
@@ -63,6 +64,7 @@ cc_library(
         ":debugging_internal",
         ":demangle_internal",
         "//absl/base",
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:dynamic_annotations",
         "//absl/base:malloc_internal",
@@ -106,6 +108,7 @@ cc_library(
     deps = [
         ":stacktrace",
         ":symbolize",
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:raw_logging_internal",
     ],
@@ -168,6 +171,7 @@ cc_library(
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:dynamic_annotations",
         "//absl/base:raw_logging_internal",
@@ -181,6 +185,7 @@ cc_library(
     copts = ABSL_DEFAULT_COPTS,
     deps = [
         "//absl/base",
+        "//absl/base:config",
         "//absl/base:core_headers",
     ],
 )
@@ -205,7 +210,10 @@ cc_library(
     srcs = ["leak_check.cc"],
     hdrs = ["leak_check.h"],
     linkopts = ABSL_DEFAULT_LINKOPTS,
-    deps = ["//absl/base:core_headers"],
+    deps = [
+        "//absl/base:config",
+        "//absl/base:core_headers",
+    ],
 )
 
 # Adding a dependency to leak_check_disable will disable
@@ -216,6 +224,7 @@ cc_library(
     srcs = ["leak_check_disable.cc"],
     linkopts = ABSL_DEFAULT_LINKOPTS,
     linkstatic = 1,
+    deps = ["//absl/base:config"],
     alwayslink = 1,
 )
 
@@ -237,6 +246,9 @@ cc_library(
     }),
     linkopts = ABSL_DEFAULT_LINKOPTS,
     visibility = ["//visibility:private"],
+    deps = [
+        "//absl/base:config",
+    ],
 )
 
 cc_library(
@@ -247,6 +259,9 @@ cc_library(
     copts = ["-ULEAK_SANITIZER"],
     linkopts = ABSL_DEFAULT_LINKOPTS,
     visibility = ["//visibility:private"],
+    deps = [
+        "//absl/base:config",
+    ],
 )
 
 cc_test(
@@ -304,6 +319,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     visibility = ["//visibility:private"],
     deps = [
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:raw_logging_internal",
     ],
diff --git a/absl/debugging/CMakeLists.txt b/absl/debugging/CMakeLists.txt
index eff504b4..ef9e71fc 100644
--- a/absl/debugging/CMakeLists.txt
+++ b/absl/debugging/CMakeLists.txt
@@ -25,6 +25,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   DEPS
     absl::debugging_internal
+    absl::config
     absl::core_headers
   PUBLIC
 )
@@ -49,6 +50,7 @@ absl_cc_library(
     absl::debugging_internal
     absl::demangle_internal
     absl::base
+    absl::config
     absl::core_headers
     absl::dynamic_annotations
     absl::malloc_internal
@@ -88,6 +90,7 @@ absl_cc_library(
   DEPS
     absl::stacktrace
     absl::symbolize
+    absl::config
     absl::core_headers
     absl::raw_logging_internal
 )
@@ -151,6 +154,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   DEPS
     absl::core_headers
+    absl::config
     absl::dynamic_annotations
     absl::raw_logging_internal
 )
@@ -196,6 +200,7 @@ absl_cc_library(
   COPTS
     ${ABSL_DEFAULT_COPTS}
   DEPS
+    absl::config
     absl::core_headers
   PUBLIC
 )
@@ -293,6 +298,7 @@ absl_cc_library(
   COPTS
     ${ABSL_DEFAULT_COPTS}
   DEPS
+    absl::config
     absl::core_headers
     absl::raw_logging_internal
   TESTONLY
diff --git a/absl/debugging/failure_signal_handler.cc b/absl/debugging/failure_signal_handler.cc
index c6a4d962..470d6768 100644
--- a/absl/debugging/failure_signal_handler.cc
+++ b/absl/debugging/failure_signal_handler.cc
@@ -47,6 +47,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 ABSL_CONST_INIT static FailureSignalHandlerOptions fsh_options;
 
@@ -356,4 +357,5 @@ void InstallFailureSignalHandler(const FailureSignalHandlerOptions& options) {
   }
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/failure_signal_handler.h b/absl/debugging/failure_signal_handler.h
index 1beb78b9..f5a83962 100644
--- a/absl/debugging/failure_signal_handler.h
+++ b/absl/debugging/failure_signal_handler.h
@@ -44,7 +44,10 @@
 #ifndef ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
 #define ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // FailureSignalHandlerOptions
 //
@@ -112,6 +115,7 @@ namespace debugging_internal {
 const char* FailureSignalToString(int signo);
 }  // namespace debugging_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_FAILURE_SIGNAL_HANDLER_H_
diff --git a/absl/debugging/internal/address_is_readable.cc b/absl/debugging/internal/address_is_readable.cc
index 99c4c64b..f45e59b3 100644
--- a/absl/debugging/internal/address_is_readable.cc
+++ b/absl/debugging/internal/address_is_readable.cc
@@ -20,12 +20,14 @@
 #if !defined(__linux__) || defined(__ANDROID__)
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // On platforms other than Linux, just return true.
 bool AddressIsReadable(const void* /* addr */) { return true; }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else
@@ -40,6 +42,7 @@ bool AddressIsReadable(const void* /* addr */) { return true; }
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Pack a pid and two file descriptors into a 64-bit word,
@@ -128,6 +131,7 @@ bool AddressIsReadable(const void *addr) {
 }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif
diff --git a/absl/debugging/internal/address_is_readable.h b/absl/debugging/internal/address_is_readable.h
index ca8003e6..4bbaf4d6 100644
--- a/absl/debugging/internal/address_is_readable.h
+++ b/absl/debugging/internal/address_is_readable.h
@@ -15,7 +15,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
 #define ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Return whether the byte at *addr is readable, without faulting.
@@ -23,6 +26,7 @@ namespace debugging_internal {
 bool AddressIsReadable(const void *addr);
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
diff --git a/absl/debugging/internal/demangle.cc b/absl/debugging/internal/demangle.cc
index 3809e496..fc615c3f 100644
--- a/absl/debugging/internal/demangle.cc
+++ b/absl/debugging/internal/demangle.cc
@@ -24,6 +24,7 @@
 #include <limits>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 typedef struct {
@@ -1890,4 +1891,5 @@ bool Demangle(const char *mangled, char *out, int out_size) {
 }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/demangle.h b/absl/debugging/internal/demangle.h
index 81bb0dfd..c314d9bc 100644
--- a/absl/debugging/internal/demangle.h
+++ b/absl/debugging/internal/demangle.h
@@ -53,7 +53,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
 #define ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Demangle `mangled`.  On success, return true and write the
@@ -62,6 +65,7 @@ namespace debugging_internal {
 bool Demangle(const char *mangled, char *out, int out_size);
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
diff --git a/absl/debugging/internal/demangle_test.cc b/absl/debugging/internal/demangle_test.cc
index a68ce324..c6f1ce18 100644
--- a/absl/debugging/internal/demangle_test.cc
+++ b/absl/debugging/internal/demangle_test.cc
@@ -23,6 +23,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -190,4 +191,5 @@ TEST(DemangleRegression, DeeplyNestedArrayType) {
 
 }  // namespace
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/elf_mem_image.cc b/absl/debugging/internal/elf_mem_image.cc
index e7408bca..24cc0130 100644
--- a/absl/debugging/internal/elf_mem_image.cc
+++ b/absl/debugging/internal/elf_mem_image.cc
@@ -38,6 +38,7 @@
 #define VERSYM_VERSION 0x7fff
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 namespace {
@@ -375,6 +376,7 @@ void ElfMemImage::SymbolIterator::Update(int increment) {
 }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE
diff --git a/absl/debugging/internal/elf_mem_image.h b/absl/debugging/internal/elf_mem_image.h
index d84200db..46bfade3 100644
--- a/absl/debugging/internal/elf_mem_image.h
+++ b/absl/debugging/internal/elf_mem_image.h
@@ -23,6 +23,8 @@
 // used.
 #include <climits>
 
+#include "absl/base/config.h"
+
 // Maybe one day we can rewrite this file not to require the elf
 // symbol extensions in glibc, but for right now we need them.
 #ifdef ABSL_HAVE_ELF_MEM_IMAGE
@@ -39,6 +41,7 @@
 #include <link.h>  // for ElfW
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // An in-memory ELF image (may not exist on disk).
@@ -123,6 +126,7 @@ class ElfMemImage {
 };
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE
diff --git a/absl/debugging/internal/examine_stack.cc b/absl/debugging/internal/examine_stack.cc
index 1ebc788f..22f41b46 100644
--- a/absl/debugging/internal/examine_stack.cc
+++ b/absl/debugging/internal/examine_stack.cc
@@ -30,6 +30,7 @@
 #include "absl/debugging/symbolize.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the program counter from signal context, nullptr if
@@ -150,4 +151,5 @@ void DumpPCAndFrameSizesAndStackTrace(
 }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/examine_stack.h b/absl/debugging/internal/examine_stack.h
index 56c9763e..39336913 100644
--- a/absl/debugging/internal/examine_stack.h
+++ b/absl/debugging/internal/examine_stack.h
@@ -17,7 +17,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
 #define ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the program counter from signal context, or nullptr if
@@ -33,6 +36,7 @@ void DumpPCAndFrameSizesAndStackTrace(
     void (*writerfn)(const char*, void*), void* writerfn_arg);
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
diff --git a/absl/debugging/internal/stack_consumption.cc b/absl/debugging/internal/stack_consumption.cc
index d4703264..875ca6d9 100644
--- a/absl/debugging/internal/stack_consumption.cc
+++ b/absl/debugging/internal/stack_consumption.cc
@@ -27,6 +27,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -177,6 +178,7 @@ int GetSignalHandlerStackConsumption(void (*signal_handler)(int)) {
 }
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stack_consumption.h b/absl/debugging/internal/stack_consumption.h
index b860a3c1..5e60ec42 100644
--- a/absl/debugging/internal/stack_consumption.h
+++ b/absl/debugging/internal/stack_consumption.h
@@ -18,6 +18,8 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_STACK_CONSUMPTION_H_
 #define ABSL_DEBUGGING_INTERNAL_STACK_CONSUMPTION_H_
 
+#include "absl/base/config.h"
+
 // The code in this module is not portable.
 // Use this feature test macro to detect its availability.
 #ifdef ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
@@ -27,6 +29,7 @@
 #define ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION 1
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the stack consumption in bytes for the code exercised by
@@ -38,6 +41,7 @@ namespace debugging_internal {
 int GetSignalHandlerStackConsumption(void (*signal_handler)(int));
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stack_consumption_test.cc b/absl/debugging/internal/stack_consumption_test.cc
index 68bfa126..80445bf4 100644
--- a/absl/debugging/internal/stack_consumption_test.cc
+++ b/absl/debugging/internal/stack_consumption_test.cc
@@ -23,6 +23,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -43,6 +44,7 @@ TEST(SignalHandlerStackConsumptionTest, MeasuresStackConsumption) {
 
 }  // namespace
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stacktrace_aarch64-inl.inc b/absl/debugging/internal/stacktrace_aarch64-inl.inc
index 7ed6b3eb..411ea308 100644
--- a/absl/debugging/internal/stacktrace_aarch64-inl.inc
+++ b/absl/debugging/internal/stacktrace_aarch64-inl.inc
@@ -180,11 +180,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_AARCH64_INL_H_
diff --git a/absl/debugging/internal/stacktrace_arm-inl.inc b/absl/debugging/internal/stacktrace_arm-inl.inc
index c8408337..fffda968 100644
--- a/absl/debugging/internal/stacktrace_arm-inl.inc
+++ b/absl/debugging/internal/stacktrace_arm-inl.inc
@@ -113,11 +113,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_
diff --git a/absl/debugging/internal/stacktrace_generic-inl.inc b/absl/debugging/internal/stacktrace_generic-inl.inc
index 81a49ef2..ac034c9f 100644
--- a/absl/debugging/internal/stacktrace_generic-inl.inc
+++ b/absl/debugging/internal/stacktrace_generic-inl.inc
@@ -87,11 +87,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_GENERIC_INL_H_
diff --git a/absl/debugging/internal/stacktrace_powerpc-inl.inc b/absl/debugging/internal/stacktrace_powerpc-inl.inc
index 3a070ee4..2e7c2f40 100644
--- a/absl/debugging/internal/stacktrace_powerpc-inl.inc
+++ b/absl/debugging/internal/stacktrace_powerpc-inl.inc
@@ -236,11 +236,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_POWERPC_INL_H_
diff --git a/absl/debugging/internal/stacktrace_unimplemented-inl.inc b/absl/debugging/internal/stacktrace_unimplemented-inl.inc
index e256fdd4..5b8fb191 100644
--- a/absl/debugging/internal/stacktrace_unimplemented-inl.inc
+++ b/absl/debugging/internal/stacktrace_unimplemented-inl.inc
@@ -12,11 +12,13 @@ static int UnwindImpl(void** /* result */, int* /* sizes */,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_UNIMPLEMENTED_INL_H_
diff --git a/absl/debugging/internal/stacktrace_win32-inl.inc b/absl/debugging/internal/stacktrace_win32-inl.inc
index 247e7428..9c2c5580 100644
--- a/absl/debugging/internal/stacktrace_win32-inl.inc
+++ b/absl/debugging/internal/stacktrace_win32-inl.inc
@@ -73,11 +73,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_WIN32_INL_H_
diff --git a/absl/debugging/internal/stacktrace_x86-inl.inc b/absl/debugging/internal/stacktrace_x86-inl.inc
index 9494441e..972febdd 100644
--- a/absl/debugging/internal/stacktrace_x86-inl.inc
+++ b/absl/debugging/internal/stacktrace_x86-inl.inc
@@ -330,11 +330,13 @@ static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_X86_INL_INC_
diff --git a/absl/debugging/internal/symbolize.h b/absl/debugging/internal/symbolize.h
index 3e537893..5d0858b5 100644
--- a/absl/debugging/internal/symbolize.h
+++ b/absl/debugging/internal/symbolize.h
@@ -21,6 +21,8 @@
 #include <cstddef>
 #include <cstdint>
 
+#include "absl/base/config.h"
+
 #ifdef ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 #error ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE cannot be directly set
 #elif defined(__ELF__) && defined(__GLIBC__) && !defined(__native_client__) && \
@@ -33,6 +35,7 @@
 #include <string>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Iterates over all sections, invoking callback on each with the section name
@@ -51,11 +54,13 @@ bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
                             ElfW(Shdr) *out);
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 struct SymbolDecoratorArgs {
@@ -117,6 +122,7 @@ bool GetFileMappingHint(const void** start,
                         const char** filename);
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_
diff --git a/absl/debugging/internal/vdso_support.cc b/absl/debugging/internal/vdso_support.cc
index d13ef25d..1e8a78ac 100644
--- a/absl/debugging/internal/vdso_support.cc
+++ b/absl/debugging/internal/vdso_support.cc
@@ -38,6 +38,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 ABSL_CONST_INIT
@@ -187,6 +188,7 @@ static class VDSOInitHelper {
 } vdso_init_helper;
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_VDSO_SUPPORT
diff --git a/absl/debugging/internal/vdso_support.h b/absl/debugging/internal/vdso_support.h
index 9895b48d..6562c6c2 100644
--- a/absl/debugging/internal/vdso_support.h
+++ b/absl/debugging/internal/vdso_support.h
@@ -53,6 +53,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // NOTE: this class may be used from within tcmalloc, and can not
@@ -149,6 +150,7 @@ class VDSOSupport {
 int GetCPU();
 
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE
diff --git a/absl/debugging/leak_check.cc b/absl/debugging/leak_check.cc
index ffe3d1bd..ff904955 100644
--- a/absl/debugging/leak_check.cc
+++ b/absl/debugging/leak_check.cc
@@ -21,12 +21,14 @@
 #ifndef LEAK_SANITIZER
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 bool HaveLeakSanitizer() { return false; }
 void DoIgnoreLeak(const void*) { }
 void RegisterLivePointers(const void*, size_t) { }
 void UnRegisterLivePointers(const void*, size_t) { }
 LeakCheckDisabler::LeakCheckDisabler() { }
 LeakCheckDisabler::~LeakCheckDisabler() { }
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else
@@ -34,6 +36,7 @@ LeakCheckDisabler::~LeakCheckDisabler() { }
 #include <sanitizer/lsan_interface.h>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 bool HaveLeakSanitizer() { return true; }
 void DoIgnoreLeak(const void* ptr) { __lsan_ignore_object(ptr); }
 void RegisterLivePointers(const void* ptr, size_t size) {
@@ -44,6 +47,7 @@ void UnRegisterLivePointers(const void* ptr, size_t size) {
 }
 LeakCheckDisabler::LeakCheckDisabler() { __lsan_disable(); }
 LeakCheckDisabler::~LeakCheckDisabler() { __lsan_enable(); }
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // LEAK_SANITIZER
diff --git a/absl/debugging/leak_check.h b/absl/debugging/leak_check.h
index 4d489c58..7a5a22dd 100644
--- a/absl/debugging/leak_check.h
+++ b/absl/debugging/leak_check.h
@@ -32,7 +32,10 @@
 
 #include <cstddef>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // HaveLeakSanitizer()
 //
@@ -104,6 +107,7 @@ void RegisterLivePointers(const void* ptr, size_t size);
 // `RegisterLivePointers()`, enabling leak checking of those pointers.
 void UnRegisterLivePointers(const void* ptr, size_t size);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_LEAK_CHECK_H_
diff --git a/absl/debugging/stacktrace.cc b/absl/debugging/stacktrace.cc
index 9de8782f..1f7c7d82 100644
--- a/absl/debugging/stacktrace.cc
+++ b/absl/debugging/stacktrace.cc
@@ -57,6 +57,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 typedef int (*Unwinder)(void**, int*, int, int, const void*, int*);
@@ -135,4 +136,5 @@ int DefaultStackUnwinder(void** pcs, int* sizes, int depth, int skip,
   return n;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/stacktrace.h b/absl/debugging/stacktrace.h
index cd8fae76..0ec0ffda 100644
--- a/absl/debugging/stacktrace.h
+++ b/absl/debugging/stacktrace.h
@@ -31,7 +31,10 @@
 #ifndef ABSL_DEBUGGING_STACKTRACE_H_
 #define ABSL_DEBUGGING_STACKTRACE_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // GetStackFrames()
 //
@@ -222,6 +225,7 @@ namespace debugging_internal {
 // working.
 extern bool StackTraceWorksForTest();
 }  // namespace debugging_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_STACKTRACE_H_
diff --git a/absl/debugging/symbolize.h b/absl/debugging/symbolize.h
index a73dbd9e..a8ff3740 100644
--- a/absl/debugging/symbolize.h
+++ b/absl/debugging/symbolize.h
@@ -55,6 +55,7 @@
 #include "absl/debugging/internal/symbolize.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // InitializeSymbolizer()
 //
@@ -92,6 +93,7 @@ void InitializeSymbolizer(const char* argv0);
 //  }
 bool Symbolize(const void *pc, char *out, int out_size);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_SYMBOLIZE_H_
diff --git a/absl/debugging/symbolize_elf.inc b/absl/debugging/symbolize_elf.inc
index 14f0c972..c371635f 100644
--- a/absl/debugging/symbolize_elf.inc
+++ b/absl/debugging/symbolize_elf.inc
@@ -76,6 +76,7 @@
 #include "absl/debugging/internal/vdso_support.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Value of argv[0]. Used by MaybeInitializeObjFile().
 static char *argv0_value = nullptr;
@@ -1475,4 +1476,5 @@ bool Symbolize(const void *pc, char *out, int out_size) {
   return ok;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/symbolize_unimplemented.inc b/absl/debugging/symbolize_unimplemented.inc
index 7c580fe4..db24456b 100644
--- a/absl/debugging/symbolize_unimplemented.inc
+++ b/absl/debugging/symbolize_unimplemented.inc
@@ -17,6 +17,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace debugging_internal {
 
@@ -35,4 +36,5 @@ bool GetFileMappingHint(const void **, const void **, uint64_t *, const char **)
 void InitializeSymbolizer(const char*) {}
 bool Symbolize(const void *, char *, int) { return false; }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/symbolize_win32.inc b/absl/debugging/symbolize_win32.inc
index bd6fbd5e..c3df46f6 100644
--- a/absl/debugging/symbolize_win32.inc
+++ b/absl/debugging/symbolize_win32.inc
@@ -31,6 +31,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 static HANDLE process = NULL;
 
@@ -76,4 +77,5 @@ bool Symbolize(const void* pc, char* out, int out_size) {
   return true;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/declare.h b/absl/flags/declare.h
index 4926a09e..f7509ce7 100644
--- a/absl/flags/declare.h
+++ b/absl/flags/declare.h
@@ -28,6 +28,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // absl::Flag<T> represents a flag of type 'T' created by ABSL_FLAG.
@@ -47,6 +48,7 @@ template <typename T>
 using Flag = flags_internal::Flag<T>;
 #endif
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // ABSL_DECLARE_FLAG()
diff --git a/absl/flags/flag.cc b/absl/flags/flag.cc
index 37bbce23..7faa7ade 100644
--- a/absl/flags/flag.cc
+++ b/absl/flags/flag.cc
@@ -18,6 +18,7 @@
 #include <cstring>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // We want to validate the type mismatch between type definition and
 // declaration. The lock-free implementation does not allow us to do it,
@@ -55,4 +56,5 @@ absl::Mutex* GetGlobalConstructionGuard() { return &construction_guard; }
 
 #endif
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/flag.h b/absl/flags/flag.h
index 52c3cede..b6fbd116 100644
--- a/absl/flags/flag.h
+++ b/absl/flags/flag.h
@@ -38,6 +38,7 @@
 #include "absl/flags/marshalling.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Flag
 //
@@ -219,6 +220,7 @@ void SetFlag(absl::Flag<T>* flag, const V& v) {
   flag->Set(value);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 
diff --git a/absl/flags/flag_test_defs.cc b/absl/flags/flag_test_defs.cc
index 3366c580..49f91dee 100644
--- a/absl/flags/flag_test_defs.cc
+++ b/absl/flags/flag_test_defs.cc
@@ -20,3 +20,5 @@
 
 ABSL_FLAG(int, mistyped_int_flag, 0, "");
 ABSL_FLAG(std::string, mistyped_string_flag, "", "");
+ABSL_RETIRED_FLAG(bool, old_bool_flag, true,
+                  "repetition of retired flag definition");
diff --git a/absl/flags/internal/commandlineflag.cc b/absl/flags/internal/commandlineflag.cc
index 88f91e16..09249274 100644
--- a/absl/flags/internal/commandlineflag.cc
+++ b/absl/flags/internal/commandlineflag.cc
@@ -18,6 +18,7 @@
 #include "absl/flags/usage_config.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // The help message indicating that the commandline flag has been
@@ -57,4 +58,5 @@ std::string CommandLineFlag::Filename() const {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/commandlineflag.h b/absl/flags/internal/commandlineflag.h
index 7964f1bf..49e13d1e 100644
--- a/absl/flags/internal/commandlineflag.h
+++ b/absl/flags/internal/commandlineflag.h
@@ -23,6 +23,7 @@
 #include "absl/types/optional.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // Type-specific operations, eg., parsing, copying, etc. are provided
@@ -158,7 +159,7 @@ class CommandLineFlag {
       : name_(name), filename_(filename) {}
 
   // Virtual destructor
-  virtual void Destroy() const = 0;
+  virtual void Destroy() = 0;
 
   // Not copyable/assignable.
   CommandLineFlag(const CommandLineFlag&) = delete;
@@ -280,6 +281,7 @@ class CommandLineFlag {
   A(float)
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_COMMANDLINEFLAG_H_
diff --git a/absl/flags/internal/flag.cc b/absl/flags/internal/flag.cc
index 435cc362..599bd7a4 100644
--- a/absl/flags/internal/flag.cc
+++ b/absl/flags/internal/flag.cc
@@ -19,6 +19,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 namespace {
 
@@ -34,20 +35,40 @@ bool ShouldValidateFlagValue(const CommandLineFlag& flag) {
   return true;
 }
 
+// RAII helper used to temporarily unlock and relock `absl::Mutex`.
+// This is used when we need to ensure that locks are released while
+// invoking user supplied callbacks and then reacquired, since callbacks may
+// need to acquire these locks themselves.
+class MutexRelock {
+ public:
+  explicit MutexRelock(absl::Mutex* mu) : mu_(mu) { mu_->Unlock(); }
+  ~MutexRelock() { mu_->Lock(); }
+
+  MutexRelock(const MutexRelock&) = delete;
+  MutexRelock& operator=(const MutexRelock&) = delete;
+
+ private:
+  absl::Mutex* mu_;
+};
+
+// This global lock guards the initialization and destruction of data_guard_,
+// which is used to guard the other Flag data.
+ABSL_CONST_INIT static absl::Mutex flag_mutex_lifetime_guard(absl::kConstInit);
+
 }  // namespace
 
 void FlagImpl::Init() {
-  ABSL_CONST_INIT static absl::Mutex init_lock(absl::kConstInit);
-
   {
-    absl::MutexLock lock(&init_lock);
+    absl::MutexLock lock(&flag_mutex_lifetime_guard);
 
-    if (locks_ == nullptr) {  // Must initialize Mutexes for this flag.
-      locks_ = new FlagImpl::CommandLineFlagLocks;
+    // Must initialize data guard for this flag.
+    if (!is_data_guard_inited_) {
+      new (&data_guard_) absl::Mutex;
+      is_data_guard_inited_ = true;
     }
   }
 
-  absl::MutexLock lock(&locks_->primary_mu);
+  absl::MutexLock lock(reinterpret_cast<absl::Mutex*>(&data_guard_));
 
   if (cur_ != nullptr) {
     inited_.store(true, std::memory_order_release);
@@ -67,21 +88,29 @@ absl::Mutex* FlagImpl::DataGuard() const {
     const_cast<FlagImpl*>(this)->Init();
   }
 
-  // All fields initialized; locks_ is therefore safe to read.
-  return &locks_->primary_mu;
+  // data_guard_ is initialized.
+  return reinterpret_cast<absl::Mutex*>(&data_guard_);
 }
 
-void FlagImpl::Destroy() const {
+void FlagImpl::Destroy() {
   {
     absl::MutexLock l(DataGuard());
 
     // Values are heap allocated for Abseil Flags.
     if (cur_) Delete(op_, cur_);
-    if (def_kind_ == FlagDefaultSrcKind::kDynamicValue)
+
+    // Release the dynamically allocated default value if any.
+    if (def_kind_ == FlagDefaultSrcKind::kDynamicValue) {
       Delete(op_, default_src_.dynamic_value);
+    }
+
+    // If this flag has an assigned callback, release callback data.
+    if (callback_data_) delete callback_data_;
   }
 
-  delete locks_;
+  absl::MutexLock l(&flag_mutex_lifetime_guard);
+  DataGuard()->~Mutex();
+  is_data_guard_inited_ = false;
 }
 
 std::unique_ptr<void, DynValueDeleter> FlagImpl::MakeInitValue() const {
@@ -126,13 +155,20 @@ void FlagImpl::SetCallback(
     const flags_internal::FlagCallback mutation_callback) {
   absl::MutexLock l(DataGuard());
 
-  callback_ = mutation_callback;
+  if (callback_data_ == nullptr) {
+    callback_data_ = new CallbackData;
+  }
+  callback_data_->func = mutation_callback;
 
   InvokeCallback();
 }
 
 void FlagImpl::InvokeCallback() const {
-  if (!callback_) return;
+  if (!callback_data_) return;
+
+  // Make a copy of the C-style function pointer that we are about to invoke
+  // before we release the lock guarding it.
+  FlagCallback cb = callback_data_->func;
 
   // If the flag has a mutation callback this function invokes it. While the
   // callback is being invoked the primary flag's mutex is unlocked and it is
@@ -145,14 +181,9 @@ void FlagImpl::InvokeCallback() const {
   // and it also can be different by the time the callback invocation is
   // completed. Requires that *primary_lock be held in exclusive mode; it may be
   // released and reacquired by the implementation.
-  DataGuard()->Unlock();
-
-  {
-    absl::MutexLock lock(&locks_->callback_mu);
-    callback_();
-  }
-
-  DataGuard()->Lock();
+  MutexRelock relock(DataGuard());
+  absl::MutexLock lock(&callback_data_->guard);
+  cb();
 }
 
 bool FlagImpl::RestoreState(const CommandLineFlag& flag, const void* value,
@@ -177,12 +208,13 @@ bool FlagImpl::RestoreState(const CommandLineFlag& flag, const void* value,
 }
 
 // Attempts to parse supplied `value` string using parsing routine in the `flag`
-// argument. If parsing successful, this function stores the parsed value in
-// 'dst' assuming it is a pointer to the flag's value type. In case if any error
-// is encountered in either step, the error message is stored in 'err'
-bool FlagImpl::TryParse(const CommandLineFlag& flag, void* dst,
+// argument. If parsing successful, this function replaces the dst with newly
+// parsed value. In case if any error is encountered in either step, the error
+// message is stored in 'err'
+bool FlagImpl::TryParse(const CommandLineFlag& flag, void** dst,
                         absl::string_view value, std::string* err) const {
   auto tentative_value = MakeInitValue();
+
   std::string parse_err;
   if (!Parse(marshalling_op_, value, tentative_value.get(), &parse_err)) {
     auto type_name = flag.Typename();
@@ -194,7 +226,10 @@ bool FlagImpl::TryParse(const CommandLineFlag& flag, void* dst,
     return false;
   }
 
-  Copy(op_, tentative_value.get(), dst);
+  void* old_val = *dst;
+  *dst = tentative_value.release();
+  tentative_value.reset(old_val);
+
   return true;
 }
 
@@ -274,7 +309,7 @@ bool FlagImpl::SetFromString(const CommandLineFlag& flag,
   switch (set_mode) {
     case SET_FLAGS_VALUE: {
       // set or modify the flag's value
-      if (!TryParse(flag, cur_, value, err)) return false;
+      if (!TryParse(flag, &cur_, value, err)) return false;
       modified_ = true;
       counter_++;
       StoreAtomic();
@@ -288,7 +323,7 @@ bool FlagImpl::SetFromString(const CommandLineFlag& flag,
     case SET_FLAG_IF_DEFAULT: {
       // set the flag's value, but only if it hasn't been set by someone else
       if (!modified_) {
-        if (!TryParse(flag, cur_, value, err)) return false;
+        if (!TryParse(flag, &cur_, value, err)) return false;
         modified_ = true;
         counter_++;
         StoreAtomic();
@@ -305,18 +340,19 @@ bool FlagImpl::SetFromString(const CommandLineFlag& flag,
       break;
     }
     case SET_FLAGS_DEFAULT: {
-      // Flag's new default-value.
-      auto new_default_value = MakeInitValue();
-
-      if (!TryParse(flag, new_default_value.get(), value, err)) return false;
-
       if (def_kind_ == FlagDefaultSrcKind::kDynamicValue) {
-        // Release old default value.
-        Delete(op_, default_src_.dynamic_value);
-      }
+        if (!TryParse(flag, &default_src_.dynamic_value, value, err)) {
+          return false;
+        }
+      } else {
+        void* new_default_val = nullptr;
+        if (!TryParse(flag, &new_default_val, value, err)) {
+          return false;
+        }
 
-      default_src_.dynamic_value = new_default_value.release();
-      def_kind_ = FlagDefaultSrcKind::kDynamicValue;
+        default_src_.dynamic_value = new_default_val;
+        def_kind_ = FlagDefaultSrcKind::kDynamicValue;
+      }
 
       if (!modified_) {
         // Need to set both default value *and* current, in this case
@@ -361,4 +397,5 @@ bool FlagImpl::ValidateInputValue(absl::string_view value) const {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/flag.h b/absl/flags/internal/flag.h
index 947a8cad..20de406f 100644
--- a/absl/flags/internal/flag.h
+++ b/absl/flags/internal/flag.h
@@ -27,6 +27,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 constexpr int64_t AtomicInit() { return 0xababababababababll; }
@@ -156,10 +157,11 @@ class FlagImpl {
         help_(help.source),
         help_source_kind_(help.kind),
         def_kind_(flags_internal::FlagDefaultSrcKind::kGenFunc),
-        default_src_(default_value_gen) {}
+        default_src_(default_value_gen),
+        data_guard_{} {}
 
   // Forces destruction of the Flag's data.
-  void Destroy() const;
+  void Destroy();
 
   // Constant access methods
   std::string Help() const;
@@ -170,9 +172,10 @@ class FlagImpl {
   void Read(const CommandLineFlag& flag, void* dst,
             const flags_internal::FlagOpFn dst_op) const
       ABSL_LOCKS_EXCLUDED(*DataGuard());
-  // Attempts to parse supplied `value` std::string.
-  bool TryParse(const CommandLineFlag& flag, void* dst, absl::string_view value,
-                std::string* err) const
+  // Attempts to parse supplied `value` std::string. If parsing is successful, then
+  // it replaces `dst` with the new value.
+  bool TryParse(const CommandLineFlag& flag, void** dst,
+                absl::string_view value, std::string* err) const
       ABSL_EXCLUSIVE_LOCKS_REQUIRED(*DataGuard());
   template <typename T>
   bool AtomicGet(T* v) const {
@@ -226,8 +229,7 @@ class FlagImpl {
   void Init();
   // Ensures that the lazily initialized data is initialized,
   // and returns pointer to the mutex guarding flags data.
-  absl::Mutex* DataGuard() const ABSL_LOCK_RETURNED(locks_->primary_mu);
-
+  absl::Mutex* DataGuard() const ABSL_LOCK_RETURNED((absl::Mutex*)&data_guard_);
   // Returns heap allocated value of type T initialized with default value.
   std::unique_ptr<void, DynValueDeleter> MakeInitValue() const
       ABSL_EXCLUSIVE_LOCKS_REQUIRED(*DataGuard());
@@ -239,9 +241,12 @@ class FlagImpl {
   // Indicates if help message was supplied as literal or generator func.
   const FlagHelpSrcKind help_source_kind_;
 
-  // Mutable Flag's data. (guarded by DataGuard()).
-  // Indicates that locks_ and cur_ fields have been lazily initialized.
+  // Indicates that the Flag state is initialized.
   std::atomic<bool> inited_{false};
+  // Mutable Flag state (guarded by data_guard_).
+  // Additional bool to protect against multiple concurrent constructions
+  // of `data_guard_`.
+  bool is_data_guard_inited_ = false;
   // Has flag value been modified?
   bool modified_ ABSL_GUARDED_BY(*DataGuard()) = false;
   // Specified on command line.
@@ -261,22 +266,20 @@ class FlagImpl {
   // For some types, a copy of the current value is kept in an atomically
   // accessible field.
   std::atomic<int64_t> atomic_{flags_internal::AtomicInit()};
-  // Mutation callback
-  FlagCallback callback_ = nullptr;
-
-  // Lazily initialized mutexes for this flag value.  We cannot inline a
-  // SpinLock or Mutex here because those have non-constexpr constructors and
-  // so would prevent constant initialization of this type.
-  // TODO(rogeeff): fix it once Mutex has constexpr constructor
-  // The following struct contains the locks in a CommandLineFlag struct.
-  // They are in a separate struct that is lazily allocated to avoid problems
-  // with static initialization and to avoid multiple allocations.
-  struct CommandLineFlagLocks {
-    absl::Mutex primary_mu;   // protects several fields in CommandLineFlag
-    absl::Mutex callback_mu;  // used to serialize callbacks
-  };
 
-  CommandLineFlagLocks* locks_ = nullptr;  // locks, laziliy allocated.
+  struct CallbackData {
+    FlagCallback func;
+    absl::Mutex guard;  // Guard for concurrent callback invocations.
+  };
+  CallbackData* callback_data_ ABSL_GUARDED_BY(*DataGuard()) = nullptr;
+  // This is reserved space for an absl::Mutex to guard flag data. It will be
+  // initialized in FlagImpl::Init via placement new.
+  // We can't use "absl::Mutex data_guard_", since this class is not literal.
+  // We do not want to use "absl::Mutex* data_guard_", since this would require
+  // heap allocation during initialization, which is both slows program startup
+  // and can fail. Using reserved space + placement new allows us to avoid both
+  // problems.
+  alignas(absl::Mutex) mutable char data_guard_[sizeof(absl::Mutex)];
 };
 
 // This is "unspecified" implementation of absl::Flag<T> type.
@@ -354,7 +357,7 @@ class Flag final : public flags_internal::CommandLineFlag {
  private:
   friend class FlagState<T>;
 
-  void Destroy() const override { impl_.Destroy(); }
+  void Destroy() override { impl_.Destroy(); }
 
   void Read(void* dst) const override {
     impl_.Read(*this, dst, &flags_internal::FlagOps<T>);
@@ -414,6 +417,7 @@ T* MakeFromDefaultValue(EmptyBraces) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_FLAG_H_
diff --git a/absl/flags/internal/parse.h b/absl/flags/internal/parse.h
index fd3aca61..e534635b 100644
--- a/absl/flags/internal/parse.h
+++ b/absl/flags/internal/parse.h
@@ -27,6 +27,7 @@ ABSL_DECLARE_FLAG(std::vector<std::string>, tryfromenv);
 ABSL_DECLARE_FLAG(std::vector<std::string>, undefok);
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 enum class ArgvListAction { kRemoveParsedArgs, kKeepParsedArgs };
@@ -43,6 +44,7 @@ std::vector<char*> ParseCommandLineImpl(int argc, char* argv[],
                                         OnUndefinedFlag on_undef_flag);
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_PARSE_H_
diff --git a/absl/flags/internal/path_util.h b/absl/flags/internal/path_util.h
index 5615c0e6..41696377 100644
--- a/absl/flags/internal/path_util.h
+++ b/absl/flags/internal/path_util.h
@@ -20,6 +20,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // A portable interface that returns the basename of the filename passed as an
@@ -55,6 +56,7 @@ inline absl::string_view Package(absl::string_view filename) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_PATH_UTIL_H_
diff --git a/absl/flags/internal/program_name.cc b/absl/flags/internal/program_name.cc
index f0811f14..df0c3309 100644
--- a/absl/flags/internal/program_name.cc
+++ b/absl/flags/internal/program_name.cc
@@ -21,6 +21,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 ABSL_CONST_INIT static absl::Mutex program_name_guard(absl::kConstInit);
@@ -50,4 +51,5 @@ void SetProgramInvocationName(absl::string_view prog_name_str) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/program_name.h b/absl/flags/internal/program_name.h
index 326f24bb..317a7c5c 100644
--- a/absl/flags/internal/program_name.h
+++ b/absl/flags/internal/program_name.h
@@ -24,6 +24,7 @@
 // Program name
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // Returns program invocation name or "UNKNOWN" if `SetProgramInvocationName()`
@@ -42,6 +43,7 @@ std::string ShortProgramInvocationName();
 void SetProgramInvocationName(absl::string_view prog_name_str);
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_PROGRAM_NAME_H_
diff --git a/absl/flags/internal/registry.cc b/absl/flags/internal/registry.cc
index 52d9f3c7..5eae933c 100644
--- a/absl/flags/internal/registry.cc
+++ b/absl/flags/internal/registry.cc
@@ -30,6 +30,7 @@
 //    set it.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // --------------------------------------------------------------------
@@ -281,7 +282,7 @@ class RetiredFlagObj final : public flags_internal::CommandLineFlag {
         op_(ops) {}
 
  private:
-  void Destroy() const override {
+  void Destroy() override {
     // Values are heap allocated for Retired Flags.
     delete this;
   }
@@ -336,4 +337,5 @@ bool IsRetiredFlag(absl::string_view name, bool* type_is_bool) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/registry.h b/absl/flags/internal/registry.h
index 1889f3a0..d2145a8a 100644
--- a/absl/flags/internal/registry.h
+++ b/absl/flags/internal/registry.h
@@ -27,6 +27,7 @@
 // Global flags registry API.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 CommandLineFlag* FindCommandLineFlag(absl::string_view name);
@@ -115,6 +116,7 @@ class FlagSaver {
 };
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_REGISTRY_H_
diff --git a/absl/flags/internal/type_erased.cc b/absl/flags/internal/type_erased.cc
index a1650fcf..7910db8f 100644
--- a/absl/flags/internal/type_erased.cc
+++ b/absl/flags/internal/type_erased.cc
@@ -21,6 +21,7 @@
 #include "absl/strings/str_cat.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 bool GetCommandLineOption(absl::string_view name, std::string* value) {
@@ -79,4 +80,5 @@ bool SpecifiedOnCommandLine(absl::string_view name) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/type_erased.h b/absl/flags/internal/type_erased.h
index a9551166..6cbd84cd 100644
--- a/absl/flags/internal/type_erased.h
+++ b/absl/flags/internal/type_erased.h
@@ -25,6 +25,7 @@
 // Registry interfaces operating on type erased handles.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // If a flag named "name" exists, store its current value in *OUTPUT
@@ -81,6 +82,7 @@ inline bool GetByName(absl::string_view name, T* dst) {
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_INTERNAL_TYPE_ERASED_H_
diff --git a/absl/flags/internal/usage.cc b/absl/flags/internal/usage.cc
index dc12e32f..4602c019 100644
--- a/absl/flags/internal/usage.cc
+++ b/absl/flags/internal/usage.cc
@@ -44,6 +44,7 @@ ABSL_FLAG(std::string, helpmatch, "",
           "show help on modules whose name contains the specified substr");
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 namespace {
 
@@ -404,4 +405,5 @@ int HandleUsageFlags(std::ostream& out,
 }
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/internal/usage.h b/absl/flags/internal/usage.h
index 76075b08..5e8ca6a1 100644
--- a/absl/flags/internal/usage.h
+++ b/absl/flags/internal/usage.h
@@ -27,6 +27,7 @@
 // Usage reporting interfaces
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // The format to report the help messages in.
@@ -64,6 +65,7 @@ int HandleUsageFlags(std::ostream& out,
                      absl::string_view program_usage_message);
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 ABSL_DECLARE_FLAG(bool, help);
diff --git a/absl/flags/marshalling.cc b/absl/flags/marshalling.cc
index f4ebe0e3..87020a27 100644
--- a/absl/flags/marshalling.cc
+++ b/absl/flags/marshalling.cc
@@ -27,6 +27,7 @@
 #include "absl/strings/str_split.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // --------------------------------------------------------------------
@@ -226,4 +227,5 @@ std::string AbslUnparseFlag(absl::LogSeverity v) {
   return absl::UnparseFlag(static_cast<int>(v));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/marshalling.h b/absl/flags/marshalling.h
index 6d391804..b9fca752 100644
--- a/absl/flags/marshalling.h
+++ b/absl/flags/marshalling.h
@@ -168,6 +168,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 // Overloads of `AbslParseFlag()` and `AbslUnparseFlag()` for fundamental types.
@@ -256,6 +257,7 @@ enum class LogSeverity : int;
 bool AbslParseFlag(absl::string_view, absl::LogSeverity*, std::string*);
 std::string AbslUnparseFlag(absl::LogSeverity);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_MARSHALLING_H_
diff --git a/absl/flags/parse.cc b/absl/flags/parse.cc
index 16c4d68f..5a56a356 100644
--- a/absl/flags/parse.cc
+++ b/absl/flags/parse.cc
@@ -38,6 +38,7 @@
 // --------------------------------------------------------------------
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 namespace {
 
@@ -52,6 +53,7 @@ ABSL_CONST_INIT bool tryfromenv_needs_processing
 
 }  // namespace
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 ABSL_FLAG(std::vector<std::string>, flagfile, {},
@@ -109,6 +111,7 @@ ABSL_FLAG(std::vector<std::string>, undefok, {},
           "with that name");
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 namespace {
@@ -748,4 +751,5 @@ std::vector<char*> ParseCommandLine(int argc, char* argv[]) {
       flags_internal::OnUndefinedFlag::kAbortIfUndefined);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/parse.h b/absl/flags/parse.h
index dbb75101..871fc993 100644
--- a/absl/flags/parse.h
+++ b/absl/flags/parse.h
@@ -29,6 +29,7 @@
 #include "absl/flags/internal/parse.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // ParseCommandLine()
 //
@@ -53,6 +54,7 @@ namespace absl {
 // help messages and then exits the program.
 std::vector<char*> ParseCommandLine(int argc, char* argv[]);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_PARSE_H_
diff --git a/absl/flags/usage.cc b/absl/flags/usage.cc
index dff7a3da..60459bc2 100644
--- a/absl/flags/usage.cc
+++ b/absl/flags/usage.cc
@@ -20,6 +20,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 namespace {
 ABSL_CONST_INIT absl::Mutex usage_message_guard(absl::kConstInit);
@@ -53,4 +54,5 @@ absl::string_view ProgramUsageMessage() {
              : "Warning: SetProgramUsageMessage() never called";
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/usage.h b/absl/flags/usage.h
index 3a121071..299e5c34 100644
--- a/absl/flags/usage.h
+++ b/absl/flags/usage.h
@@ -22,6 +22,7 @@
 // Usage reporting interfaces
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Sets the "usage" message to be used by help reporting routines.
 // For example:
@@ -35,6 +36,7 @@ void SetProgramUsageMessage(absl::string_view new_usage_message);
 // Returns the usage message set by SetProgramUsageMessage().
 absl::string_view ProgramUsageMessage();
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FLAGS_USAGE_H_
diff --git a/absl/flags/usage_config.cc b/absl/flags/usage_config.cc
index f97bf300..21a2dd01 100644
--- a/absl/flags/usage_config.cc
+++ b/absl/flags/usage_config.cc
@@ -34,6 +34,7 @@ ABSL_ATTRIBUTE_WEAK void AbslInternalReportFatalUsageError(absl::string_view) {}
 }  // extern "C"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace flags_internal {
 
 namespace {
@@ -149,4 +150,5 @@ void SetFlagsUsageConfig(FlagsUsageConfig usage_config) {
     flags_internal::custom_usage_config = new FlagsUsageConfig(usage_config);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/flags/usage_config.h b/absl/flags/usage_config.h
index bfd0eedb..e6428e0a 100644
--- a/absl/flags/usage_config.h
+++ b/absl/flags/usage_config.h
@@ -54,6 +54,7 @@
 //     Shows help on modules whose name contains the specified substring
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace flags_internal {
 using FlagKindFilter = std::function<bool (absl::string_view)>;
@@ -118,6 +119,7 @@ FlagsUsageConfig GetUsageConfig();
 void ReportUsageError(absl::string_view msg, bool is_fatal);
 
 }  // namespace flags_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 extern "C" {
diff --git a/absl/functional/function_ref.h b/absl/functional/function_ref.h
index 42d9f16f..370acc55 100644
--- a/absl/functional/function_ref.h
+++ b/absl/functional/function_ref.h
@@ -54,6 +54,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // FunctionRef
 //
@@ -132,6 +133,7 @@ class FunctionRef<R(Args...)> {
   absl::functional_internal::Invoker<R, Args...> invoker_;
 };
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FUNCTIONAL_FUNCTION_REF_H_
diff --git a/absl/functional/function_ref_benchmark.cc b/absl/functional/function_ref_benchmark.cc
index f6dfcabf..045305bf 100644
--- a/absl/functional/function_ref_benchmark.cc
+++ b/absl/functional/function_ref_benchmark.cc
@@ -20,6 +20,7 @@
 #include "absl/base/attributes.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 int dummy = 0;
@@ -137,4 +138,5 @@ void BM_NonTrivialArgsFunctionRef(benchmark::State& state) {
 BENCHMARK(BM_NonTrivialArgsFunctionRef);
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/functional/function_ref_test.cc b/absl/functional/function_ref_test.cc
index 90829db0..3aa59745 100644
--- a/absl/functional/function_ref_test.cc
+++ b/absl/functional/function_ref_test.cc
@@ -22,6 +22,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 void RunFun(FunctionRef<void()> f) { f(); }
@@ -252,4 +253,5 @@ TEST(FunctionRef, PassByValueTypes) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/functional/internal/function_ref.h b/absl/functional/internal/function_ref.h
index fcb0496c..d1575054 100644
--- a/absl/functional/internal/function_ref.h
+++ b/absl/functional/internal/function_ref.h
@@ -23,6 +23,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace functional_internal {
 
 // Like a void* that can handle function pointers as well. The standard does not
@@ -99,6 +100,7 @@ template <bool C>
 using EnableIf = typename ::std::enable_if<C, int>::type;
 
 }  // namespace functional_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_FUNCTIONAL_INTERNAL_FUNCTION_REF_H_
diff --git a/absl/hash/hash.h b/absl/hash/hash.h
index 297dc9cb..23a65ea8 100644
--- a/absl/hash/hash.h
+++ b/absl/hash/hash.h
@@ -73,6 +73,7 @@
 #include "absl/hash/internal/hash.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // `absl::Hash`
@@ -317,6 +318,7 @@ class HashState : public hash_internal::HashStateBase<HashState> {
   void (*combine_contiguous_)(void*, const unsigned char*, size_t);
 };
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HASH_HASH_H_
diff --git a/absl/hash/hash_test.cc b/absl/hash/hash_test.cc
index 42c0c3d8..7a9d57f7 100644
--- a/absl/hash/hash_test.cc
+++ b/absl/hash/hash_test.cc
@@ -681,6 +681,7 @@ H AbslHashValue(H state, CustomHashType<Tags...> t) {
 }  // namespace
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 template <InvokeTag... Tags>
 struct is_uniquely_represented<
@@ -688,6 +689,7 @@ struct is_uniquely_represented<
     typename EnableIfContained<InvokeTag::kUniquelyRepresented, Tags...>::type>
     : std::true_type {};
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #if ABSL_HASH_INTERNAL_SUPPORT_LEGACY_HASH_
diff --git a/absl/hash/hash_testing.h b/absl/hash/hash_testing.h
index c45bc154..1e1c5741 100644
--- a/absl/hash/hash_testing.h
+++ b/absl/hash/hash_testing.h
@@ -28,6 +28,7 @@
 #include "absl/types/variant.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Run the absl::Hash algorithm over all the elements passed in and verify that
 // their hash expansion is congruent with their `==` operator.
@@ -371,6 +372,7 @@ VerifyTypeImplementsAbslHashCorrectly(std::initializer_list<T> values,
       equals);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HASH_HASH_TESTING_H_
diff --git a/absl/hash/internal/city.cc b/absl/hash/internal/city.cc
index dc7650a7..e122c184 100644
--- a/absl/hash/internal/city.cc
+++ b/absl/hash/internal/city.cc
@@ -30,6 +30,7 @@
 #include "absl/base/optimization.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 #ifdef ABSL_IS_BIG_ENDIAN
@@ -341,4 +342,5 @@ uint64_t CityHash64WithSeeds(const char *s, size_t len, uint64_t seed0,
 }
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/hash/internal/city.h b/absl/hash/internal/city.h
index b43d3407..161c7748 100644
--- a/absl/hash/internal/city.h
+++ b/absl/hash/internal/city.h
@@ -47,9 +47,13 @@
 
 #include <stdint.h>
 #include <stdlib.h>  // for size_t.
+
 #include <utility>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 typedef std::pair<uint64_t, uint64_t> uint128;
@@ -86,6 +90,7 @@ inline uint64_t Hash128to64(const uint128 &x) {
 }
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HASH_INTERNAL_CITY_H_
diff --git a/absl/hash/internal/city_test.cc b/absl/hash/internal/city_test.cc
index 71b4ecce..251d381d 100644
--- a/absl/hash/internal/city_test.cc
+++ b/absl/hash/internal/city_test.cc
@@ -20,6 +20,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 static const uint64_t k0 = 0xc3a5c85c97cb3127ULL;
@@ -590,4 +591,5 @@ TEST(CityHashTest, Unchanging) {
 }
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/hash/internal/hash.cc b/absl/hash/internal/hash.cc
index c17f3be1..b44ecb3a 100644
--- a/absl/hash/internal/hash.cc
+++ b/absl/hash/internal/hash.cc
@@ -15,6 +15,7 @@
 #include "absl/hash/internal/hash.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 uint64_t CityHashState::CombineLargeContiguousImpl32(uint64_t state,
@@ -50,4 +51,5 @@ uint64_t CityHashState::CombineLargeContiguousImpl64(uint64_t state,
 ABSL_CONST_INIT const void* const CityHashState::kSeed = &kSeed;
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/hash/internal/hash.h b/absl/hash/internal/hash.h
index 7d44f57d..2564978a 100644
--- a/absl/hash/internal/hash.h
+++ b/absl/hash/internal/hash.h
@@ -50,6 +50,7 @@
 #include "absl/hash/internal/city.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 class PiecewiseCombiner;
@@ -980,6 +981,7 @@ H PiecewiseCombiner::finalize(H state) {
 }
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HASH_INTERNAL_HASH_H_
diff --git a/absl/hash/internal/spy_hash_state.h b/absl/hash/internal/spy_hash_state.h
index 05c7cafe..c0831208 100644
--- a/absl/hash/internal/spy_hash_state.h
+++ b/absl/hash/internal/spy_hash_state.h
@@ -25,6 +25,7 @@
 #include "absl/strings/str_join.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace hash_internal {
 
 // SpyHashState is an implementation of the HashState API that simply
@@ -224,6 +225,7 @@ void AbslHashValue(SpyHashStateImpl<T>, const U&);
 using SpyHashState = SpyHashStateImpl<void>;
 
 }  // namespace hash_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HASH_INTERNAL_SPY_HASH_STATE_H_
diff --git a/absl/memory/memory.h b/absl/memory/memory.h
index 243a5dda..513f7103 100644
--- a/absl/memory/memory.h
+++ b/absl/memory/memory.h
@@ -34,6 +34,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // Function Template: WrapUnique()
@@ -688,6 +689,7 @@ void CopyRange(Allocator& alloc, Iterator destination, InputIterator first,
   }
 }
 }  // namespace memory_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_MEMORY_MEMORY_H_
diff --git a/absl/memory/memory_exception_safety_test.cc b/absl/memory/memory_exception_safety_test.cc
index 729507e9..c0910dc7 100644
--- a/absl/memory/memory_exception_safety_test.cc
+++ b/absl/memory/memory_exception_safety_test.cc
@@ -22,6 +22,7 @@
 #include "absl/base/internal/exception_safety_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 constexpr int kLength = 50;
@@ -53,6 +54,7 @@ TEST(MakeUnique, CheckForLeaks) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_EXCEPTIONS
diff --git a/absl/meta/type_traits.h b/absl/meta/type_traits.h
index 8cd5f043..ba87d2f0 100644
--- a/absl/meta/type_traits.h
+++ b/absl/meta/type_traits.h
@@ -48,6 +48,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Defined and documented later on in this file.
 template <typename T>
@@ -752,6 +753,7 @@ using swap_internal::Swap;
 using swap_internal::StdSwapIsUnconstrained;
 
 }  // namespace type_traits_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_META_TYPE_TRAITS_H_
diff --git a/absl/numeric/int128.cc b/absl/numeric/int128.cc
index 1eba09de..a20a77e7 100644
--- a/absl/numeric/int128.cc
+++ b/absl/numeric/int128.cc
@@ -23,6 +23,7 @@
 #include <type_traits>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 const uint128 kuint128max = MakeUint128(std::numeric_limits<uint64_t>::max(),
                                         std::numeric_limits<uint64_t>::max());
@@ -349,6 +350,7 @@ std::ostream& operator<<(std::ostream& os, int128 v) {
   return os << rep;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 namespace std {
diff --git a/absl/numeric/int128.h b/absl/numeric/int128.h
index 50617612..718f70b1 100644
--- a/absl/numeric/int128.h
+++ b/absl/numeric/int128.h
@@ -49,6 +49,7 @@
 #endif  // defined(_MSC_VER)
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class int128;
 
@@ -245,6 +246,7 @@ constexpr uint128 Uint128Max() {
                  (std::numeric_limits<uint64_t>::max)());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // Specialized numeric_limits for uint128.
@@ -293,6 +295,7 @@ class numeric_limits<absl::uint128> {
 }  // namespace std
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // int128
 //
@@ -478,6 +481,7 @@ constexpr int128 Int128Min() {
   return int128((std::numeric_limits<int64_t>::min)(), 0);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // Specialized numeric_limits for int128.
@@ -529,6 +533,7 @@ class numeric_limits<absl::int128> {
 //                      Implementation details follow
 // --------------------------------------------------------------------------
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 constexpr uint128 MakeUint128(uint64_t high, uint64_t low) {
   return uint128(high, low);
@@ -1078,6 +1083,7 @@ constexpr int64_t BitCastToSigned(uint64_t v) {
 #include "absl/numeric/int128_no_intrinsic.inc"  // IWYU pragma: export
 #endif  // ABSL_HAVE_INTRINSIC_INT128
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_INTERNAL_WCHAR_T
diff --git a/absl/random/CMakeLists.txt b/absl/random/CMakeLists.txt
index 13e96357..46dbc3ef 100644
--- a/absl/random/CMakeLists.txt
+++ b/absl/random/CMakeLists.txt
@@ -526,6 +526,8 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -559,6 +561,8 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -618,6 +622,8 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::config
   TESTONLY
 )
 
@@ -631,6 +637,8 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::config
   TESTONLY
 )
 
@@ -782,6 +790,8 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
+  DEPS
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -816,6 +826,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_LINKOPTS}
   DEPS
     absl::random_internal_platform
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -835,6 +846,7 @@ absl_cc_library(
   DEPS
     absl::random_internal_platform
     absl::random_internal_randen_hwaes_impl
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -851,6 +863,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_LINKOPTS}
   DEPS
     absl::random_internal_platform
+    absl::config
 )
 
 # Internal-only target, do not depend on directly.
@@ -868,6 +881,7 @@ absl_cc_library(
   LINKOPTS
     ${ABSL_DEFAULT_LINKOPTS}
   DEPS
+    absl::config
     absl::core_headers
     absl::raw_logging_internal
     absl::strings
diff --git a/absl/random/bernoulli_distribution.h b/absl/random/bernoulli_distribution.h
index 326fcb6e..25bd0d5c 100644
--- a/absl/random/bernoulli_distribution.h
+++ b/absl/random/bernoulli_distribution.h
@@ -24,6 +24,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::bernoulli_distribution is a drop in replacement for
 // std::bernoulli_distribution. It guarantees that (given a perfect
@@ -193,6 +194,7 @@ bool bernoulli_distribution::Generate(double p,
   }
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_BERNOULLI_DISTRIBUTION_H_
diff --git a/absl/random/beta_distribution.h b/absl/random/beta_distribution.h
index b09b02f0..c154066f 100644
--- a/absl/random/beta_distribution.h
+++ b/absl/random/beta_distribution.h
@@ -29,6 +29,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::beta_distribution:
 // Generate a floating-point variate conforming to a Beta distribution:
@@ -420,6 +421,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_BETA_DISTRIBUTION_H_
diff --git a/absl/random/bit_gen_ref.h b/absl/random/bit_gen_ref.h
index 00e904f8..e8771162 100644
--- a/absl/random/bit_gen_ref.h
+++ b/absl/random/bit_gen_ref.h
@@ -31,6 +31,7 @@
 #include "absl/random/internal/mocking_bit_gen_base.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 template <typename URBG, typename = void, typename = void, typename = void>
@@ -146,6 +147,7 @@ struct DistributionCaller<absl::BitGenRef> {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_BIT_GEN_REF_H_
diff --git a/absl/random/bit_gen_ref_test.cc b/absl/random/bit_gen_ref_test.cc
index bc02ca5c..ca0e4d70 100644
--- a/absl/random/bit_gen_ref_test.cc
+++ b/absl/random/bit_gen_ref_test.cc
@@ -21,6 +21,7 @@
 #include "absl/random/random.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class ConstBitGen : public absl::random_internal::MockingBitGenBase {
   bool CallImpl(const std::type_info&, void*, void* result) override {
@@ -96,4 +97,5 @@ TEST(BitGenRefTest, MockingBitGenBaseOverrides) {
   EXPECT_EQ(FnTest(gen_ref), 42);  // Copy
 }
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/discrete_distribution.cc b/absl/random/discrete_distribution.cc
index e6c09c51..081accee 100644
--- a/absl/random/discrete_distribution.cc
+++ b/absl/random/discrete_distribution.cc
@@ -15,6 +15,7 @@
 #include "absl/random/discrete_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Initializes the distribution table for Walker's Aliasing algorithm, described
@@ -93,4 +94,5 @@ std::vector<std::pair<double, size_t>> InitDiscreteDistribution(
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/discrete_distribution.h b/absl/random/discrete_distribution.h
index 1560f03c..171aa11a 100644
--- a/absl/random/discrete_distribution.h
+++ b/absl/random/discrete_distribution.h
@@ -29,6 +29,7 @@
 #include "absl/random/uniform_int_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::discrete_distribution
 //
@@ -240,6 +241,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_DISCRETE_DISTRIBUTION_H_
diff --git a/absl/random/distribution_format_traits.h b/absl/random/distribution_format_traits.h
index f9f07058..22b358cc 100644
--- a/absl/random/distribution_format_traits.h
+++ b/absl/random/distribution_format_traits.h
@@ -36,6 +36,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 struct IntervalClosedClosedTag;
 struct IntervalClosedOpenTag;
@@ -271,6 +272,7 @@ struct DistributionFormatTraits<UniformDistributionWrapper<NumType>> {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_DISTRIBUTION_FORMAT_TRAITS_H_
diff --git a/absl/random/distributions.h b/absl/random/distributions.h
index 6ced6061..c1fb6650 100644
--- a/absl/random/distributions.h
+++ b/absl/random/distributions.h
@@ -67,6 +67,7 @@
 #include "absl/random/zipf_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 ABSL_INTERNAL_INLINE_CONSTEXPR(IntervalClosedClosedTag, IntervalClosedClosed,
                                {});
@@ -458,6 +459,7 @@ IntType Zipf(URBG&& urbg,  // NOLINT(runtime/references)
       distribution_t, format_t>(&urbg, hi, q, v);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_DISTRIBUTIONS_H_
diff --git a/absl/random/exponential_distribution.h b/absl/random/exponential_distribution.h
index 24abf57e..b5caf8a1 100644
--- a/absl/random/exponential_distribution.h
+++ b/absl/random/exponential_distribution.h
@@ -27,6 +27,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::exponential_distribution:
 // Generates a number conforming to an exponential distribution and is
@@ -158,6 +159,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_EXPONENTIAL_DISTRIBUTION_H_
diff --git a/absl/random/gaussian_distribution.cc b/absl/random/gaussian_distribution.cc
index 5dd84619..c7a72cb2 100644
--- a/absl/random/gaussian_distribution.cc
+++ b/absl/random/gaussian_distribution.cc
@@ -4,6 +4,7 @@
 #include "absl/random/gaussian_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 const gaussian_distribution_base::Tables
@@ -96,6 +97,7 @@ const gaussian_distribution_base::Tables
      0.9362826816850632339, 0.9635996931270905952, 1}};
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // clang-format on
diff --git a/absl/random/gaussian_distribution.h b/absl/random/gaussian_distribution.h
index c299e944..c1427b06 100644
--- a/absl/random/gaussian_distribution.h
+++ b/absl/random/gaussian_distribution.h
@@ -33,6 +33,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // absl::gaussian_distribution_base implements the underlying ziggurat algorithm
@@ -267,6 +268,7 @@ inline double gaussian_distribution_base::zignor(
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_GAUSSIAN_DISTRIBUTION_H_
diff --git a/absl/random/internal/BUILD.bazel b/absl/random/internal/BUILD.bazel
index 952929ea..d7ad4efe 100644
--- a/absl/random/internal/BUILD.bazel
+++ b/absl/random/internal/BUILD.bazel
@@ -51,6 +51,7 @@ cc_library(
     visibility = [
         "//absl/random:__pkg__",
     ],
+    deps = ["//absl/base:config"],
 )
 
 cc_library(
@@ -78,6 +79,7 @@ cc_library(
     visibility = [
         "//absl/random:__pkg__",
     ],
+    deps = ["//absl/base:config"],
 )
 
 cc_library(
@@ -138,6 +140,7 @@ cc_library(
     ],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = ["//absl/base:config"],
 )
 
 cc_library(
@@ -148,6 +151,7 @@ cc_library(
     ],
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
+    deps = ["//absl/base:config"],
 )
 
 cc_library(
@@ -269,6 +273,7 @@ cc_library(
         "randen-keys.inc",
         "platform.h",
     ],
+    deps = ["//absl/base:config"],
 )
 
 cc_library(
@@ -297,6 +302,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":platform",
+        "//absl/base:config",
         "//absl/base:core_headers",
     ],
 )
@@ -317,6 +323,7 @@ cc_library(
     deps = [
         ":platform",
         ":randen_hwaes_impl",
+        "//absl/base:config",
     ],
 )
 
@@ -338,6 +345,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":platform",
+        "//absl/base:config",
         "//absl/base:core_headers",
     ],
 )
@@ -368,6 +376,7 @@ cc_library(
     copts = ABSL_DEFAULT_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:raw_logging_internal",
         "//absl/strings",
diff --git a/absl/random/internal/chi_square.cc b/absl/random/internal/chi_square.cc
index c0acc947..640d48ce 100644
--- a/absl/random/internal/chi_square.cc
+++ b/absl/random/internal/chi_square.cc
@@ -19,6 +19,7 @@
 #include "absl/random/internal/distribution_test_util.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -227,4 +228,5 @@ double ChiSquarePValue(double chi_square, int dof) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/chi_square.h b/absl/random/internal/chi_square.h
index fa8646f2..07f4fbe5 100644
--- a/absl/random/internal/chi_square.h
+++ b/absl/random/internal/chi_square.h
@@ -26,7 +26,10 @@
 
 #include <cassert>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 constexpr const char kChiSquared[] = "chi-squared";
@@ -80,6 +83,7 @@ double ChiSquareValue(int dof, double p);
 double ChiSquarePValue(double chi_square, int dof);
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_CHI_SQUARE_H_
diff --git a/absl/random/internal/distribution_caller.h b/absl/random/internal/distribution_caller.h
index 0318e1f8..02603cf8 100644
--- a/absl/random/internal/distribution_caller.h
+++ b/absl/random/internal/distribution_caller.h
@@ -19,7 +19,10 @@
 
 #include <utility>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // DistributionCaller provides an opportunity to overload the general
@@ -51,6 +54,7 @@ struct DistributionCaller {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_DISTRIBUTION_CALLER_H_
diff --git a/absl/random/internal/distribution_test_util.cc b/absl/random/internal/distribution_test_util.cc
index 85c8d596..e9005658 100644
--- a/absl/random/internal/distribution_test_util.cc
+++ b/absl/random/internal/distribution_test_util.cc
@@ -25,6 +25,7 @@
 #include "absl/strings/str_format.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -413,4 +414,5 @@ double MaxErrorTolerance(double acceptance_probability) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/distribution_test_util.h b/absl/random/internal/distribution_test_util.h
index b5ba49fa..6d94cf6c 100644
--- a/absl/random/internal/distribution_test_util.h
+++ b/absl/random/internal/distribution_test_util.h
@@ -26,6 +26,7 @@
 // non-test code.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // http://webspace.ship.edu/pgmarr/Geo441/Lectures/Lec%205%20-%20Normality%20Testing.pdf
@@ -106,6 +107,7 @@ double BetaIncomplete(double x, double p, double q);
 double BetaIncompleteInv(double p, double q, double alpha);
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_DISTRIBUTION_TEST_UTIL_H_
diff --git a/absl/random/internal/distributions.h b/absl/random/internal/distributions.h
index c8cec02b..d7e3c016 100644
--- a/absl/random/internal/distributions.h
+++ b/absl/random/internal/distributions.h
@@ -23,6 +23,7 @@
 #include "absl/random/internal/uniform_helper.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // In the absence of an explicitly provided return-type, the template
@@ -45,6 +46,7 @@ using uniform_inferred_return_t =
                           is_widening_convertible<A, B>::value, B, A>::type>;
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_DISTRIBUTIONS_H_
diff --git a/absl/random/internal/explicit_seed_seq.h b/absl/random/internal/explicit_seed_seq.h
index b660ece5..6a743eaf 100644
--- a/absl/random/internal/explicit_seed_seq.h
+++ b/absl/random/internal/explicit_seed_seq.h
@@ -22,7 +22,10 @@
 #include <iterator>
 #include <vector>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // This class conforms to the C++ Standard "Seed Sequence" concept
@@ -82,6 +85,7 @@ class ExplicitSeedSeq {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_EXPLICIT_SEED_SEQ_H_
diff --git a/absl/random/internal/fast_uniform_bits.h b/absl/random/internal/fast_uniform_bits.h
index e8df92f3..f13c8729 100644
--- a/absl/random/internal/fast_uniform_bits.h
+++ b/absl/random/internal/fast_uniform_bits.h
@@ -20,7 +20,10 @@
 #include <limits>
 #include <type_traits>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 // Returns true if the input value is zero or a power of two. Useful for
 // determining if the range of output values in a URBG
@@ -255,6 +258,7 @@ FastUniformBits<UIntType>::Generate(URBG& g,  // NOLINT(runtime/references)
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_FAST_UNIFORM_BITS_H_
diff --git a/absl/random/internal/fast_uniform_bits_test.cc b/absl/random/internal/fast_uniform_bits_test.cc
index 9f2e8268..f5b837e5 100644
--- a/absl/random/internal/fast_uniform_bits_test.cc
+++ b/absl/random/internal/fast_uniform_bits_test.cc
@@ -19,6 +19,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -269,4 +270,5 @@ TEST(FastUniformBitsTest, URBG32bitRegression) {
 
 }  // namespace
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/fastmath.h b/absl/random/internal/fastmath.h
index 4bd18410..6baeb5a7 100644
--- a/absl/random/internal/fastmath.h
+++ b/absl/random/internal/fastmath.h
@@ -25,6 +25,7 @@
 #include "absl/base/internal/bits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Returns the position of the first bit set.
@@ -67,6 +68,7 @@ inline constexpr uint64_t rotr(uint64_t value, uint8_t bits) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_FASTMATH_H_
diff --git a/absl/random/internal/gaussian_distribution_gentables.cc b/absl/random/internal/gaussian_distribution_gentables.cc
index 16a23cb2..a2bf0394 100644
--- a/absl/random/internal/gaussian_distribution_gentables.cc
+++ b/absl/random/internal/gaussian_distribution_gentables.cc
@@ -27,6 +27,7 @@
 #include "absl/base/macros.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -135,6 +136,7 @@ void TableGenerator::Print(std::ostream* os) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 int main(int, char**) {
diff --git a/absl/random/internal/generate_real.h b/absl/random/internal/generate_real.h
index 246d863e..20f6d208 100644
--- a/absl/random/internal/generate_real.h
+++ b/absl/random/internal/generate_real.h
@@ -29,6 +29,7 @@
 #include "absl/random/internal/traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Tristate tag types controlling the output of GenerateRealFromBits.
@@ -139,6 +140,7 @@ inline RealType GenerateRealFromBits(uint64_t bits, int exp_bias = 0) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_GENERATE_REAL_H_
diff --git a/absl/random/internal/iostream_state_saver.h b/absl/random/internal/iostream_state_saver.h
index df88fa76..7378829a 100644
--- a/absl/random/internal/iostream_state_saver.h
+++ b/absl/random/internal/iostream_state_saver.h
@@ -24,6 +24,7 @@
 #include "absl/numeric/int128.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // The null_state_saver does nothing.
@@ -238,6 +239,7 @@ inline FloatType read_floating_point(IStream& is) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_IOSTREAM_STATE_SAVER_H_
diff --git a/absl/random/internal/mock_overload_set.h b/absl/random/internal/mock_overload_set.h
index 539313d7..c2a30d89 100644
--- a/absl/random/internal/mock_overload_set.h
+++ b/absl/random/internal/mock_overload_set.h
@@ -23,6 +23,7 @@
 #include "absl/random/mocking_bit_gen.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 template <typename DistrT, typename Fn>
@@ -85,5 +86,6 @@ struct MockOverloadSet<DistrT, FirstSig, Rest...>
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_RANDOM_INTERNAL_MOCK_OVERLOAD_SET_H_
diff --git a/absl/random/internal/mocking_bit_gen_base.h b/absl/random/internal/mocking_bit_gen_base.h
index aff2ba6d..eeeae9d2 100644
--- a/absl/random/internal/mocking_bit_gen_base.h
+++ b/absl/random/internal/mocking_bit_gen_base.h
@@ -25,6 +25,7 @@
 #include "absl/strings/str_cat.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // MockingBitGenExpectationFormatter is invoked to format unsatisfied mocks
@@ -113,6 +114,7 @@ class MockingBitGenBase {
 };  // namespace random_internal
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_MOCKING_BIT_GEN_BASE_H_
diff --git a/absl/random/internal/nanobenchmark.cc b/absl/random/internal/nanobenchmark.cc
index feb81c85..8fee77fc 100644
--- a/absl/random/internal/nanobenchmark.cc
+++ b/absl/random/internal/nanobenchmark.cc
@@ -70,6 +70,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal_nanobenchmark {
 namespace {
 
@@ -799,4 +800,5 @@ size_t Measure(const Func func, const void* arg, const FuncInput* inputs,
 }
 
 }  // namespace random_internal_nanobenchmark
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/nanobenchmark.h b/absl/random/internal/nanobenchmark.h
index c2b650d1..a5097ba2 100644
--- a/absl/random/internal/nanobenchmark.h
+++ b/absl/random/internal/nanobenchmark.h
@@ -50,7 +50,10 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal_nanobenchmark {
 
 // Input influencing the function being measured (e.g. number of bytes to copy).
@@ -163,6 +166,7 @@ static inline size_t MeasureClosure(const Closure& closure,
 }
 
 }  // namespace random_internal_nanobenchmark
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_NANOBENCHMARK_H_
diff --git a/absl/random/internal/nanobenchmark_test.cc b/absl/random/internal/nanobenchmark_test.cc
index 383345a8..ab824ef5 100644
--- a/absl/random/internal/nanobenchmark_test.cc
+++ b/absl/random/internal/nanobenchmark_test.cc
@@ -18,6 +18,7 @@
 #include "absl/strings/numbers.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal_nanobenchmark {
 namespace {
 
@@ -67,6 +68,7 @@ void RunAll(const int argc, char* argv[]) {
 
 }  // namespace
 }  // namespace random_internal_nanobenchmark
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 int main(int argc, char* argv[]) {
diff --git a/absl/random/internal/nonsecure_base.h b/absl/random/internal/nonsecure_base.h
index 8847e74b..730fa2ea 100644
--- a/absl/random/internal/nonsecure_base.h
+++ b/absl/random/internal/nonsecure_base.h
@@ -33,6 +33,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Each instance of NonsecureURBGBase<URBG> will be seeded by variates produced
@@ -143,6 +144,7 @@ class NonsecureURBGBase {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_NONSECURE_BASE_H_
diff --git a/absl/random/internal/pcg_engine.h b/absl/random/internal/pcg_engine.h
index b5df4eaf..53c23fe1 100644
--- a/absl/random/internal/pcg_engine.h
+++ b/absl/random/internal/pcg_engine.h
@@ -24,6 +24,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // pcg_engine is a simplified implementation of Melissa O'Neil's PCG engine in
@@ -300,6 +301,7 @@ using pcg32_2018_engine = pcg_engine<
     random_internal::pcg_xsh_rr_64_32>;
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_PCG_ENGINE_H_
diff --git a/absl/random/internal/pool_urbg.cc b/absl/random/internal/pool_urbg.cc
index f2e1c1f6..5bee5307 100644
--- a/absl/random/internal/pool_urbg.cc
+++ b/absl/random/internal/pool_urbg.cc
@@ -37,6 +37,7 @@ using absl::base_internal::SpinLock;
 using absl::base_internal::SpinLockHolder;
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -249,4 +250,5 @@ template class RandenPool<uint32_t>;
 template class RandenPool<uint64_t>;
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/pool_urbg.h b/absl/random/internal/pool_urbg.h
index 9b2dd4bf..05721929 100644
--- a/absl/random/internal/pool_urbg.h
+++ b/absl/random/internal/pool_urbg.h
@@ -22,6 +22,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // RandenPool is a thread-safe random number generator [random.req.urbg] that
@@ -124,6 +125,7 @@ class PoolURBG {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_POOL_URBG_H_
diff --git a/absl/random/internal/randen.cc b/absl/random/internal/randen.cc
index bab8075a..78a1e00c 100644
--- a/absl/random/internal/randen.cc
+++ b/absl/random/internal/randen.cc
@@ -41,6 +41,7 @@
 // structured/low-entropy counters to digits of Pi.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -86,4 +87,5 @@ Randen::Randen() {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/randen.h b/absl/random/internal/randen.h
index a4ff2545..c2834aaf 100644
--- a/absl/random/internal/randen.h
+++ b/absl/random/internal/randen.h
@@ -23,6 +23,7 @@
 #include "absl/random/internal/randen_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // RANDen = RANDom generator or beetroots in Swiss German.
@@ -95,6 +96,7 @@ class Randen {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_H_
diff --git a/absl/random/internal/randen_detect.cc b/absl/random/internal/randen_detect.cc
index d5946b21..d63230c2 100644
--- a/absl/random/internal/randen_detect.cc
+++ b/absl/random/internal/randen_detect.cc
@@ -95,6 +95,7 @@ static uint32_t GetAuxval(uint32_t hwcap_type) {
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // The default return at the end of the function might be unreachable depending
@@ -216,4 +217,5 @@ bool CPUSupportsRandenHwAes() {
 #endif
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/randen_detect.h b/absl/random/internal/randen_detect.h
index 44c5c667..f283f432 100644
--- a/absl/random/internal/randen_detect.h
+++ b/absl/random/internal/randen_detect.h
@@ -15,7 +15,10 @@
 #ifndef ABSL_RANDOM_INTERNAL_RANDEN_DETECT_H_
 #define ABSL_RANDOM_INTERNAL_RANDEN_DETECT_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Returns whether the current CPU supports RandenHwAes implementation.
@@ -24,6 +27,7 @@ namespace random_internal {
 bool CPUSupportsRandenHwAes();
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_DETECT_H_
diff --git a/absl/random/internal/randen_engine.h b/absl/random/internal/randen_engine.h
index 02212a13..6b337313 100644
--- a/absl/random/internal/randen_engine.h
+++ b/absl/random/internal/randen_engine.h
@@ -28,6 +28,7 @@
 #include "absl/random/internal/randen.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Deterministic pseudorandom byte generator with backtracking resistance
@@ -223,6 +224,7 @@ class alignas(16) randen_engine {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_ENGINE_H_
diff --git a/absl/random/internal/randen_hwaes.cc b/absl/random/internal/randen_hwaes.cc
index 6cc36fd3..e23844f1 100644
--- a/absl/random/internal/randen_hwaes.cc
+++ b/absl/random/internal/randen_hwaes.cc
@@ -75,6 +75,7 @@
 #include <cstdlib>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // No accelerated implementation.
@@ -106,6 +107,7 @@ void RandenHwAes::Generate(const void*, void*) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // defined(ABSL_RANDEN_HWAES_IMPL)
@@ -518,6 +520,7 @@ inline ABSL_TARGET_CRYPTO void Permute(
 }  // namespace
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 bool HasRandenHwAesImplementation() { return true; }
@@ -629,6 +632,7 @@ void ABSL_TARGET_CRYPTO RandenHwAes::Generate(const void* keys,
 #endif
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // (ABSL_RANDEN_HWAES_IMPL)
diff --git a/absl/random/internal/randen_hwaes.h b/absl/random/internal/randen_hwaes.h
index d8e6055f..bce36b52 100644
--- a/absl/random/internal/randen_hwaes.h
+++ b/absl/random/internal/randen_hwaes.h
@@ -15,12 +15,15 @@
 #ifndef ABSL_RANDOM_INTERNAL_RANDEN_HWAES_H_
 #define ABSL_RANDOM_INTERNAL_RANDEN_HWAES_H_
 
+#include "absl/base/config.h"
+
 // HERMETIC NOTE: The randen_hwaes target must not introduce duplicate
 // symbols from arbitrary system and other headers, since it may be built
 // with different flags from other targets, using different levels of
 // optimization, potentially introducing ODR violations.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // RANDen = RANDom generator or beetroots in Swiss German.
@@ -41,6 +44,7 @@ class RandenHwAes {
 bool HasRandenHwAesImplementation();
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_HWAES_H_
diff --git a/absl/random/internal/randen_slow.cc b/absl/random/internal/randen_slow.cc
index e7959c7e..8d074582 100644
--- a/absl/random/internal/randen_slow.cc
+++ b/absl/random/internal/randen_slow.cc
@@ -462,6 +462,7 @@ inline ABSL_RANDOM_INTERNAL_ATTRIBUTE_ALWAYS_INLINE void Permute(
 }  // namespace
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 const void* RandenSlow::GetKeys() {
@@ -501,4 +502,5 @@ void RandenSlow::Generate(const void* keys, void* state_void) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/randen_slow.h b/absl/random/internal/randen_slow.h
index 30586130..72f92b54 100644
--- a/absl/random/internal/randen_slow.h
+++ b/absl/random/internal/randen_slow.h
@@ -17,7 +17,10 @@
 
 #include <cstddef>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // RANDen = RANDom generator or beetroots in Swiss German.
@@ -38,6 +41,7 @@ class RandenSlow {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_SLOW_H_
diff --git a/absl/random/internal/randen_traits.h b/absl/random/internal/randen_traits.h
index 4f1f408d..2b8bbe73 100644
--- a/absl/random/internal/randen_traits.h
+++ b/absl/random/internal/randen_traits.h
@@ -22,7 +22,10 @@
 
 #include <cstddef>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // RANDen = RANDom generator or beetroots in Swiss German.
@@ -54,6 +57,7 @@ struct RandenTraits {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_RANDEN_TRAITS_H_
diff --git a/absl/random/internal/salted_seed_seq.h b/absl/random/internal/salted_seed_seq.h
index 86487006..5953a090 100644
--- a/absl/random/internal/salted_seed_seq.h
+++ b/absl/random/internal/salted_seed_seq.h
@@ -30,6 +30,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // This class conforms to the C++ Standard "Seed Sequence" concept
@@ -160,6 +161,7 @@ SaltedSeedSeq<typename std::decay<SSeq>::type> MakeSaltedSeedSeq(SSeq&& seq) {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_SALTED_SEED_SEQ_H_
diff --git a/absl/random/internal/seed_material.cc b/absl/random/internal/seed_material.cc
index ab4dd0c2..4d38a574 100644
--- a/absl/random/internal/seed_material.cc
+++ b/absl/random/internal/seed_material.cc
@@ -61,6 +61,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 namespace {
 
@@ -214,4 +215,5 @@ absl::optional<uint32_t> GetSaltMaterial() {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/internal/seed_material.h b/absl/random/internal/seed_material.h
index 57de8a24..4be10e92 100644
--- a/absl/random/internal/seed_material.h
+++ b/absl/random/internal/seed_material.h
@@ -27,6 +27,7 @@
 #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
@@ -97,6 +98,7 @@ void MixIntoSeedMaterial(absl::Span<const uint32_t> sequence,
 absl::optional<uint32_t> GetSaltMaterial();
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_SEED_MATERIAL_H_
diff --git a/absl/random/internal/sequence_urbg.h b/absl/random/internal/sequence_urbg.h
index 9a9b5773..bc96a12c 100644
--- a/absl/random/internal/sequence_urbg.h
+++ b/absl/random/internal/sequence_urbg.h
@@ -21,7 +21,10 @@
 #include <type_traits>
 #include <vector>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // `sequence_urbg` is a simple random number generator which meets the
@@ -51,6 +54,7 @@ class sequence_urbg {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_SEQUENCE_URBG_H_
diff --git a/absl/random/internal/traits.h b/absl/random/internal/traits.h
index 40eb011f..75772bd9 100644
--- a/absl/random/internal/traits.h
+++ b/absl/random/internal/traits.h
@@ -22,6 +22,7 @@
 #include "absl/base/config.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // random_internal::is_widening_convertible<A, B>
@@ -94,6 +95,7 @@ struct make_unsigned_bits {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_TRAITS_H_
diff --git a/absl/random/internal/uniform_helper.h b/absl/random/internal/uniform_helper.h
index f68b1823..663107cb 100644
--- a/absl/random/internal/uniform_helper.h
+++ b/absl/random/internal/uniform_helper.h
@@ -22,6 +22,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 template <typename IntType>
 class uniform_int_distribution;
 
@@ -173,6 +174,7 @@ struct UniformDistributionWrapper : public UniformDistribution<NumType> {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_UNIFORM_HELPER_H_
diff --git a/absl/random/internal/wide_multiply.h b/absl/random/internal/wide_multiply.h
index ebbfa1f2..6e4cf1be 100644
--- a/absl/random/internal/wide_multiply.h
+++ b/absl/random/internal/wide_multiply.h
@@ -31,6 +31,7 @@
 #include "absl/random/internal/traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace random_internal {
 
 // Helper object to multiply two 64-bit values to a 128-bit value.
@@ -104,6 +105,7 @@ struct wide_multiply<uint64_t> {
 #endif
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_INTERNAL_WIDE_MULTIPLY_H_
diff --git a/absl/random/log_uniform_int_distribution.h b/absl/random/log_uniform_int_distribution.h
index de58bdbe..960816e2 100644
--- a/absl/random/log_uniform_int_distribution.h
+++ b/absl/random/log_uniform_int_distribution.h
@@ -30,6 +30,7 @@
 #include "absl/random/uniform_int_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // log_uniform_int_distribution:
 //
@@ -247,6 +248,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_LOG_UNIFORM_INT_DISTRIBUTION_H_
diff --git a/absl/random/mock_distributions.h b/absl/random/mock_distributions.h
index 1af98a24..d36d5ba0 100644
--- a/absl/random/mock_distributions.h
+++ b/absl/random/mock_distributions.h
@@ -53,6 +53,7 @@
 #include "absl/random/mocking_bit_gen.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // absl::MockUniform
@@ -254,6 +255,7 @@ using MockZipf =
                                      IntType(MockingBitGen&, IntType, double,
                                              double)>;
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_MOCK_DISTRIBUTIONS_H_
diff --git a/absl/random/mocking_bit_gen.cc b/absl/random/mocking_bit_gen.cc
index 73144528..6bb1e414 100644
--- a/absl/random/mocking_bit_gen.cc
+++ b/absl/random/mocking_bit_gen.cc
@@ -18,6 +18,7 @@
 #include <string>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 MockingBitGen::~MockingBitGen() {
 
   for (const auto& del : deleters_) {
@@ -25,4 +26,5 @@ MockingBitGen::~MockingBitGen() {
   }
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/mocking_bit_gen.h b/absl/random/mocking_bit_gen.h
index d1b524a9..36cef911 100644
--- a/absl/random/mocking_bit_gen.h
+++ b/absl/random/mocking_bit_gen.h
@@ -51,6 +51,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace random_internal {
 
@@ -189,6 +190,7 @@ struct DistributionCaller<absl::MockingBitGen> {
 };
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_MOCKING_BIT_GEN_H_
diff --git a/absl/random/poisson_distribution.h b/absl/random/poisson_distribution.h
index 23a953ff..cb5f5d5d 100644
--- a/absl/random/poisson_distribution.h
+++ b/absl/random/poisson_distribution.h
@@ -28,6 +28,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::poisson_distribution:
 // Generates discrete variates conforming to a Poisson distribution.
@@ -251,6 +252,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_POISSON_DISTRIBUTION_H_
diff --git a/absl/random/random.h b/absl/random/random.h
index dc6852f4..c8f326e6 100644
--- a/absl/random/random.h
+++ b/absl/random/random.h
@@ -41,6 +41,7 @@
 #include "absl/random/seed_sequences.h"  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // absl::BitGen
@@ -182,6 +183,7 @@ using InsecureBitGen =
 // discards the intermediate results.
 // ---------------------------------------------------------------------------
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_RANDOM_H_
diff --git a/absl/random/seed_gen_exception.cc b/absl/random/seed_gen_exception.cc
index e4271baa..fdcb54a8 100644
--- a/absl/random/seed_gen_exception.cc
+++ b/absl/random/seed_gen_exception.cc
@@ -19,6 +19,7 @@
 #include "absl/base/config.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 static constexpr const char kExceptionMessage[] =
     "Failed generating seed-material for URBG.";
@@ -41,4 +42,5 @@ void ThrowSeedGenException() {
 }
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/seed_gen_exception.h b/absl/random/seed_gen_exception.h
index b464d52f..53539005 100644
--- a/absl/random/seed_gen_exception.h
+++ b/absl/random/seed_gen_exception.h
@@ -28,7 +28,10 @@
 
 #include <exception>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 //------------------------------------------------------------------------------
 // SeedGenException
@@ -46,6 +49,7 @@ namespace random_internal {
 [[noreturn]] void ThrowSeedGenException();
 
 }  // namespace random_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_SEED_GEN_EXCEPTION_H_
diff --git a/absl/random/seed_sequences.cc b/absl/random/seed_sequences.cc
index 9f319615..426eafd3 100644
--- a/absl/random/seed_sequences.cc
+++ b/absl/random/seed_sequences.cc
@@ -17,6 +17,7 @@
 #include "absl/random/internal/pool_urbg.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 SeedSeq MakeSeedSeq() {
   SeedSeq::result_type seed_material[8];
@@ -24,4 +25,5 @@ SeedSeq MakeSeedSeq() {
   return SeedSeq(std::begin(seed_material), std::end(seed_material));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/random/seed_sequences.h b/absl/random/seed_sequences.h
index 631d1ecd..ff1340cc 100644
--- a/absl/random/seed_sequences.h
+++ b/absl/random/seed_sequences.h
@@ -34,6 +34,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // absl::SeedSeq
@@ -103,6 +104,7 @@ SeedSeq CreateSeedSeqFrom(URBG* urbg) {
 //
 SeedSeq MakeSeedSeq();
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_SEED_SEQUENCES_H_
diff --git a/absl/random/uniform_int_distribution.h b/absl/random/uniform_int_distribution.h
index dc8ba8c1..da66564a 100644
--- a/absl/random/uniform_int_distribution.h
+++ b/absl/random/uniform_int_distribution.h
@@ -40,6 +40,7 @@
 #include "absl/random/internal/wide_multiply.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::uniform_int_distribution<T>
 //
@@ -268,6 +269,7 @@ uniform_int_distribution<IntType>::Generate(
   return helper::hi(product);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_UNIFORM_INT_DISTRIBUTION_H_
diff --git a/absl/random/uniform_real_distribution.h b/absl/random/uniform_real_distribution.h
index bf2ed2c5..5ba17b23 100644
--- a/absl/random/uniform_real_distribution.h
+++ b/absl/random/uniform_real_distribution.h
@@ -45,6 +45,7 @@
 #include "absl/random/internal/iostream_state_saver.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::uniform_real_distribution<T>
 //
@@ -195,6 +196,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   }
   return is;
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_UNIFORM_REAL_DISTRIBUTION_H_
diff --git a/absl/random/zipf_distribution.h b/absl/random/zipf_distribution.h
index d7b4ac38..22ebc756 100644
--- a/absl/random/zipf_distribution.h
+++ b/absl/random/zipf_distribution.h
@@ -26,6 +26,7 @@
 #include "absl/random/uniform_real_distribution.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::zipf_distribution produces random integer-values in the range [0, k],
 // distributed according to the discrete probability function:
@@ -264,6 +265,7 @@ std::basic_istream<CharT, Traits>& operator>>(
   return is;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_RANDOM_ZIPF_DISTRIBUTION_H_
diff --git a/absl/strings/BUILD.bazel b/absl/strings/BUILD.bazel
index e38c8ad6..8d0a6b6d 100644
--- a/absl/strings/BUILD.bazel
+++ b/absl/strings/BUILD.bazel
@@ -94,6 +94,7 @@ cc_library(
     ],
     copts = ABSL_DEFAULT_COPTS,
     deps = [
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:endian",
         "//absl/meta:type_traits",
@@ -413,6 +414,7 @@ cc_test(
     deps = [
         ":pow10_helper",
         ":strings",
+        "//absl/base:config",
         "//absl/base:raw_logging_internal",
         "//absl/random",
         "//absl/random:distributions",
@@ -489,6 +491,7 @@ cc_test(
     copts = ABSL_TEST_COPTS,
     deps = [
         ":strings",
+        "//absl/base:config",
         "//absl/base:raw_logging_internal",
         "@com_google_googletest//:gtest_main",
     ],
@@ -504,6 +507,7 @@ cc_test(
     copts = ABSL_TEST_COPTS,
     deps = [
         ":strings",
+        "//absl/base:config",
         "@com_google_googletest//:gtest_main",
     ],
 )
@@ -668,6 +672,7 @@ cc_library(
     srcs = ["internal/pow10_helper.cc"],
     hdrs = ["internal/pow10_helper.h"],
     visibility = ["//visibility:private"],
+    deps = ["//absl/base:config"],
 )
 
 cc_test(
diff --git a/absl/strings/CMakeLists.txt b/absl/strings/CMakeLists.txt
index cd52a472..98101573 100644
--- a/absl/strings/CMakeLists.txt
+++ b/absl/strings/CMakeLists.txt
@@ -81,6 +81,7 @@ absl_cc_library(
   COPTS
     ${ABSL_DEFAULT_COPTS}
   DEPS
+    absl::config
     absl::core_headers
     absl::endian
     absl::type_traits
@@ -276,6 +277,7 @@ absl_cc_test(
     absl::strings
     absl::core_headers
     absl::pow10_helper
+    absl::config
     absl::raw_logging_internal
     absl::random_random
     absl::random_distributions
@@ -331,6 +333,7 @@ absl_cc_test(
     ${ABSL_TEST_COPTS}
   DEPS
     absl::strings
+    absl::config
     absl::raw_logging_internal
     gmock_main
 )
@@ -346,6 +349,7 @@ absl_cc_test(
     ${ABSL_TEST_COPTS}
   DEPS
     absl::strings
+    absl::config
     gmock_main
 )
 
@@ -502,6 +506,8 @@ absl_cc_library(
     "internal/pow10_helper.cc"
   COPTS
     ${ABSL_TEST_COPTS}
+  DEPS
+    absl::config
   TESTONLY
 )
 
diff --git a/absl/strings/ascii.cc b/absl/strings/ascii.cc
index 3f7c581f..abea3e4f 100644
--- a/absl/strings/ascii.cc
+++ b/absl/strings/ascii.cc
@@ -15,6 +15,7 @@
 #include "absl/strings/ascii.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace ascii_internal {
 
 // # Table generated by this Python code (bit 0x02 is currently unused):
@@ -195,4 +196,5 @@ void RemoveExtraAsciiWhitespace(std::string* str) {
   str->erase(output_it - &(*str)[0]);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/ascii.h b/absl/strings/ascii.h
index f9e4fd1d..792aabe5 100644
--- a/absl/strings/ascii.h
+++ b/absl/strings/ascii.h
@@ -59,6 +59,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace ascii_internal {
 
 // Declaration for an array of bitfields holding character information.
@@ -234,6 +235,7 @@ inline void StripAsciiWhitespace(std::string* str) {
 // Removes leading, trailing, and consecutive internal whitespace.
 void RemoveExtraAsciiWhitespace(std::string*);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_ASCII_H_
diff --git a/absl/strings/charconv.cc b/absl/strings/charconv.cc
index bc07e7ab..d9bc2dd2 100644
--- a/absl/strings/charconv.cc
+++ b/absl/strings/charconv.cc
@@ -57,6 +57,7 @@
 // narrower mantissas.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 template <typename FloatType>
@@ -980,4 +981,5 @@ const int16_t kPower10ExponentTable[] = {
 };
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/charconv.h b/absl/strings/charconv.h
index 3f5891ba..e04be32f 100644
--- a/absl/strings/charconv.h
+++ b/absl/strings/charconv.h
@@ -17,7 +17,10 @@
 
 #include <system_error>  // NOLINT(build/c++11)
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Workalike compatibilty version of std::chars_format from C++17.
 //
@@ -110,6 +113,7 @@ inline chars_format& operator^=(chars_format& lhs, chars_format rhs) {
   return lhs;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_CHARCONV_H_
diff --git a/absl/strings/escaping.cc b/absl/strings/escaping.cc
index 18b746e3..d2fcd9c1 100644
--- a/absl/strings/escaping.cc
+++ b/absl/strings/escaping.cc
@@ -33,6 +33,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 // These are used for the leave_nulls_escaped argument to CUnescapeInternal().
@@ -1106,4 +1107,5 @@ std::string BytesToHexString(absl::string_view from) {
   return result;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/escaping.h b/absl/strings/escaping.h
index 198b9348..f5ca26c5 100644
--- a/absl/strings/escaping.h
+++ b/absl/strings/escaping.h
@@ -33,6 +33,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // CUnescape()
 //
@@ -157,6 +158,7 @@ std::string HexStringToBytes(absl::string_view from);
 // `2*from.size()`.
 std::string BytesToHexString(absl::string_view from);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_ESCAPING_H_
diff --git a/absl/strings/internal/char_map.h b/absl/strings/internal/char_map.h
index b9108b8c..a76e6036 100644
--- a/absl/strings/internal/char_map.h
+++ b/absl/strings/internal/char_map.h
@@ -28,6 +28,7 @@
 #include "absl/base/port.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 class Charmap {
@@ -149,6 +150,7 @@ constexpr Charmap GraphCharmap() { return PrintCharmap() & ~SpaceCharmap(); }
 constexpr Charmap PunctCharmap() { return GraphCharmap() & ~AlnumCharmap(); }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_CHAR_MAP_H_
diff --git a/absl/strings/internal/charconv_bigint.cc b/absl/strings/internal/charconv_bigint.cc
index 95d471d9..860c27b2 100644
--- a/absl/strings/internal/charconv_bigint.cc
+++ b/absl/strings/internal/charconv_bigint.cc
@@ -19,6 +19,7 @@
 #include <string>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 namespace {
@@ -354,4 +355,5 @@ template class BigUnsigned<4>;
 template class BigUnsigned<84>;
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/charconv_bigint.h b/absl/strings/internal/charconv_bigint.h
index 7da9a7e7..108e1eb2 100644
--- a/absl/strings/internal/charconv_bigint.h
+++ b/absl/strings/internal/charconv_bigint.h
@@ -25,6 +25,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // The largest power that 5 that can be raised to, and still fit in a uint32_t.
@@ -414,6 +415,7 @@ extern template class BigUnsigned<4>;
 extern template class BigUnsigned<84>;
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_CHARCONV_BIGINT_H_
diff --git a/absl/strings/internal/charconv_bigint_test.cc b/absl/strings/internal/charconv_bigint_test.cc
index 745714ac..363bcb03 100644
--- a/absl/strings/internal/charconv_bigint_test.cc
+++ b/absl/strings/internal/charconv_bigint_test.cc
@@ -19,6 +19,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 TEST(BigUnsigned, ShiftLeft) {
@@ -200,4 +201,5 @@ TEST(BigUnsigned, TenToTheNth) {
 
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/charconv_parse.cc b/absl/strings/internal/charconv_parse.cc
index fa9a8965..d9a57a78 100644
--- a/absl/strings/internal/charconv_parse.cc
+++ b/absl/strings/internal/charconv_parse.cc
@@ -22,6 +22,7 @@
 #include "absl/strings/internal/memutil.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 // ParseFloat<10> will read the first 19 significant digits of the mantissa.
@@ -499,4 +500,5 @@ template ParsedFloat ParseFloat<16>(const char* begin, const char* end,
                                     chars_format format_flags);
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/charconv_parse.h b/absl/strings/internal/charconv_parse.h
index 44d06b2e..505998b5 100644
--- a/absl/strings/internal/charconv_parse.h
+++ b/absl/strings/internal/charconv_parse.h
@@ -17,9 +17,11 @@
 
 #include <cstdint>
 
+#include "absl/base/config.h"
 #include "absl/strings/charconv.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // Enum indicating whether a parsed float is a number or special value.
@@ -92,5 +94,6 @@ extern template ParsedFloat ParseFloat<16>(const char* begin, const char* end,
                                            absl::chars_format format_flags);
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_STRINGS_INTERNAL_CHARCONV_PARSE_H_
diff --git a/absl/strings/internal/escaping_test_common.h b/absl/strings/internal/escaping_test_common.h
index bd803031..7b18017a 100644
--- a/absl/strings/internal/escaping_test_common.h
+++ b/absl/strings/internal/escaping_test_common.h
@@ -22,6 +22,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 struct base64_testcase {
@@ -126,6 +127,7 @@ inline const std::array<base64_testcase, 5>& base64_strings() {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_ESCAPING_TEST_COMMON_H_
diff --git a/absl/strings/internal/memutil.cc b/absl/strings/internal/memutil.cc
index 77aa63c2..2519c688 100644
--- a/absl/strings/internal/memutil.cc
+++ b/absl/strings/internal/memutil.cc
@@ -17,6 +17,7 @@
 #include <cstdlib>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 int memcasecmp(const char* s1, const char* s2, size_t len) {
@@ -107,4 +108,5 @@ const char* memmatch(const char* phaystack, size_t haylen, const char* pneedle,
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/memutil.h b/absl/strings/internal/memutil.h
index 7c071a82..9ad05358 100644
--- a/absl/strings/internal/memutil.h
+++ b/absl/strings/internal/memutil.h
@@ -69,6 +69,7 @@
 #include "absl/strings/ascii.h"  // for absl::ascii_tolower
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 inline char* memcat(char* dest, size_t destlen, const char* src,
@@ -141,6 +142,7 @@ const char* memmatch(const char* phaystack, size_t haylen, const char* pneedle,
                      size_t neelen);
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_MEMUTIL_H_
diff --git a/absl/strings/internal/numbers_test_common.h b/absl/strings/internal/numbers_test_common.h
index a263219e..1a1e50c4 100644
--- a/absl/strings/internal/numbers_test_common.h
+++ b/absl/strings/internal/numbers_test_common.h
@@ -23,7 +23,10 @@
 #include <limits>
 #include <string>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 template <typename IntType>
@@ -175,6 +178,7 @@ inline const std::array<uint64_test_case, 34>& strtouint64_test_cases() {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_NUMBERS_TEST_COMMON_H_
diff --git a/absl/strings/internal/ostringstream.cc b/absl/strings/internal/ostringstream.cc
index d0f0f84b..05324c78 100644
--- a/absl/strings/internal/ostringstream.cc
+++ b/absl/strings/internal/ostringstream.cc
@@ -15,6 +15,7 @@
 #include "absl/strings/internal/ostringstream.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 OStringStream::Buf::int_type OStringStream::overflow(int c) {
@@ -31,4 +32,5 @@ std::streamsize OStringStream::xsputn(const char* s, std::streamsize n) {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/ostringstream.h b/absl/strings/internal/ostringstream.h
index 20792015..d25d6047 100644
--- a/absl/strings/internal/ostringstream.h
+++ b/absl/strings/internal/ostringstream.h
@@ -23,6 +23,7 @@
 #include "absl/base/port.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // The same as std::ostringstream but appends to a user-specified std::string,
@@ -82,6 +83,7 @@ class OStringStream : private std::basic_streambuf<char>, public std::ostream {
 };
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_OSTRINGSTREAM_H_
diff --git a/absl/strings/internal/pow10_helper.cc b/absl/strings/internal/pow10_helper.cc
index 03ed8d07..42e96c34 100644
--- a/absl/strings/internal/pow10_helper.cc
+++ b/absl/strings/internal/pow10_helper.cc
@@ -17,6 +17,7 @@
 #include <cmath>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 namespace {
@@ -117,4 +118,5 @@ double Pow10(int exp) {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/pow10_helper.h b/absl/strings/internal/pow10_helper.h
index 9d1aa710..c37c2c3f 100644
--- a/absl/strings/internal/pow10_helper.h
+++ b/absl/strings/internal/pow10_helper.h
@@ -22,7 +22,10 @@
 
 #include <vector>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // Computes the precise value of 10^exp. (I.e. the nearest representable
@@ -31,6 +34,7 @@ namespace strings_internal {
 double Pow10(int exp);
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_POW10_HELPER_H_
diff --git a/absl/strings/internal/pow10_helper_test.cc b/absl/strings/internal/pow10_helper_test.cc
index a4a68b5d..a4ff76d3 100644
--- a/absl/strings/internal/pow10_helper_test.cc
+++ b/absl/strings/internal/pow10_helper_test.cc
@@ -20,6 +20,7 @@
 #include "absl/strings/str_format.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 namespace {
@@ -117,4 +118,5 @@ TEST(Pow10HelperTest, Works) {
 
 }  // namespace
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/resize_uninitialized.h b/absl/strings/internal/resize_uninitialized.h
index 0f5e964d..e42628e3 100644
--- a/absl/strings/internal/resize_uninitialized.h
+++ b/absl/strings/internal/resize_uninitialized.h
@@ -25,6 +25,7 @@
 #include "absl/meta/type_traits.h"  //  for void_t
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // Is a subclass of true_type or false_type, depending on whether or not
@@ -66,6 +67,7 @@ inline void STLStringResizeUninitialized(string_type* s, size_t new_size) {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_RESIZE_UNINITIALIZED_H_
diff --git a/absl/strings/internal/stl_type_traits.h b/absl/strings/internal/stl_type_traits.h
index 202ab374..6035ca45 100644
--- a/absl/strings/internal/stl_type_traits.h
+++ b/absl/strings/internal/stl_type_traits.h
@@ -40,6 +40,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 template <typename C, template <typename...> class T>
@@ -242,5 +243,6 @@ struct IsStrictlyBaseOfAndConvertibleToSTLContainer
                         IsConvertibleToSTLContainer<C>> {};
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_STRINGS_INTERNAL_STL_TYPE_TRAITS_H_
diff --git a/absl/strings/internal/str_format/arg.cc b/absl/strings/internal/str_format/arg.cc
index b567a5c5..875bd99c 100644
--- a/absl/strings/internal/str_format/arg.cc
+++ b/absl/strings/internal/str_format/arg.cc
@@ -14,6 +14,7 @@
 #include "absl/strings/internal/str_format/float_conversion.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 
@@ -386,4 +387,5 @@ ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_();
 
 }  // namespace str_format_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/arg.h b/absl/strings/internal/str_format/arg.h
index a209a927..b672a229 100644
--- a/absl/strings/internal/str_format/arg.h
+++ b/absl/strings/internal/str_format/arg.h
@@ -19,6 +19,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Cord;
 class FormatCountCapture;
@@ -426,6 +427,7 @@ ABSL_INTERNAL_FORMAT_DISPATCH_OVERLOADS_EXPAND_(extern);
 
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_ARG_H_
diff --git a/absl/strings/internal/str_format/arg_test.cc b/absl/strings/internal/str_format/arg_test.cc
index 3421fac1..96c9cfd3 100644
--- a/absl/strings/internal/str_format/arg_test.cc
+++ b/absl/strings/internal/str_format/arg_test.cc
@@ -14,6 +14,7 @@
 #include "absl/strings/str_format.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 
@@ -108,4 +109,5 @@ const char kMyArray[] = "ABCDE";
 
 }  // namespace
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/bind.cc b/absl/strings/internal/str_format/bind.cc
index 45e335a3..1ee281af 100644
--- a/absl/strings/internal/str_format/bind.cc
+++ b/absl/strings/internal/str_format/bind.cc
@@ -6,6 +6,7 @@
 #include <string>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 namespace {
@@ -236,4 +237,5 @@ int SnprintF(char* output, size_t size, const UntypedFormatSpecImpl format,
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/bind.h b/absl/strings/internal/str_format/bind.h
index dafcd610..2bf0c085 100644
--- a/absl/strings/internal/str_format/bind.h
+++ b/absl/strings/internal/str_format/bind.h
@@ -13,6 +13,7 @@
 #include "absl/types/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class UntypedFormatSpec;
 
@@ -202,6 +203,7 @@ class StreamedWrapper {
 };
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
diff --git a/absl/strings/internal/str_format/bind_test.cc b/absl/strings/internal/str_format/bind_test.cc
index 2574801a..f6817419 100644
--- a/absl/strings/internal/str_format/bind_test.cc
+++ b/absl/strings/internal/str_format/bind_test.cc
@@ -6,6 +6,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 
@@ -138,4 +139,5 @@ TEST_F(FormatBindTest, FormatPack) {
 
 }  // namespace
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/checker.h b/absl/strings/internal/str_format/checker.h
index 04a88827..8993a79b 100644
--- a/absl/strings/internal/str_format/checker.h
+++ b/absl/strings/internal/str_format/checker.h
@@ -14,6 +14,7 @@
 #endif  // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 constexpr bool AllOf() { return true; }
@@ -319,6 +320,7 @@ constexpr bool ValidFormatImpl(string_view format) {
 #endif  // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_CHECKER_H_
diff --git a/absl/strings/internal/str_format/checker_test.cc b/absl/strings/internal/str_format/checker_test.cc
index 7aa194a7..c309e203 100644
--- a/absl/strings/internal/str_format/checker_test.cc
+++ b/absl/strings/internal/str_format/checker_test.cc
@@ -5,6 +5,7 @@
 #include "absl/strings/str_format.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 
@@ -147,4 +148,5 @@ TEST(StrFormatChecker, LongFormat) {
 
 }  // namespace
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/convert_test.cc b/absl/strings/internal/str_format/convert_test.cc
index 5f198059..ca994346 100644
--- a/absl/strings/internal/str_format/convert_test.cc
+++ b/absl/strings/internal/str_format/convert_test.cc
@@ -11,6 +11,7 @@
 #include "absl/strings/internal/str_format/bind.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 
@@ -646,4 +647,5 @@ TEST_F(FormatConvertTest, ExpectedFailures) {
 
 }  // namespace
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/extension.cc b/absl/strings/internal/str_format/extension.cc
index d7f58159..559011bf 100644
--- a/absl/strings/internal/str_format/extension.cc
+++ b/absl/strings/internal/str_format/extension.cc
@@ -20,6 +20,7 @@
 #include <string>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 namespace {
 // clang-format off
@@ -81,4 +82,5 @@ bool FormatSinkImpl::PutPaddedString(string_view v, int w, int p, bool l) {
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/extension.h b/absl/strings/internal/str_format/extension.h
index 3f4788c9..5726ea5c 100644
--- a/absl/strings/internal/str_format/extension.h
+++ b/absl/strings/internal/str_format/extension.h
@@ -26,6 +26,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Cord;
 
@@ -406,6 +407,7 @@ inline size_t Excess(size_t used, size_t capacity) {
 
 }  // namespace str_format_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_EXTENSION_H_
diff --git a/absl/strings/internal/str_format/float_conversion.cc b/absl/strings/internal/str_format/float_conversion.cc
index 9236acdc..ebe4da5b 100644
--- a/absl/strings/internal/str_format/float_conversion.cc
+++ b/absl/strings/internal/str_format/float_conversion.cc
@@ -9,6 +9,7 @@
 #include "absl/base/config.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 namespace {
@@ -482,4 +483,5 @@ bool ConvertFloatImpl(double v, const ConversionSpec &conv,
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/float_conversion.h b/absl/strings/internal/str_format/float_conversion.h
index 8ba5566d..49a6a636 100644
--- a/absl/strings/internal/str_format/float_conversion.h
+++ b/absl/strings/internal/str_format/float_conversion.h
@@ -4,6 +4,7 @@
 #include "absl/strings/internal/str_format/extension.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 bool ConvertFloatImpl(float v, const ConversionSpec &conv,
@@ -16,6 +17,7 @@ bool ConvertFloatImpl(long double v, const ConversionSpec &conv,
                       FormatSinkImpl *sink);
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_FLOAT_CONVERSION_H_
diff --git a/absl/strings/internal/str_format/output.cc b/absl/strings/internal/str_format/output.cc
index 38987b63..c4b24706 100644
--- a/absl/strings/internal/str_format/output.cc
+++ b/absl/strings/internal/str_format/output.cc
@@ -18,6 +18,7 @@
 #include <cstring>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 namespace {
@@ -67,4 +68,5 @@ void FILERawSink::Write(string_view v) {
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/output.h b/absl/strings/internal/str_format/output.h
index 6dc2f3f7..28b288b7 100644
--- a/absl/strings/internal/str_format/output.h
+++ b/absl/strings/internal/str_format/output.h
@@ -29,6 +29,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Cord;
 
@@ -97,6 +98,7 @@ auto InvokeFlush(T* out, string_view s)
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_OUTPUT_H_
diff --git a/absl/strings/internal/str_format/output_test.cc b/absl/strings/internal/str_format/output_test.cc
index 6e04abef..e54e6f70 100644
--- a/absl/strings/internal/str_format/output_test.cc
+++ b/absl/strings/internal/str_format/output_test.cc
@@ -21,6 +21,7 @@
 #include "gtest/gtest.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 TEST(InvokeFlush, String) {
@@ -67,5 +68,6 @@ TEST(BufferRawSink, Limits) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
diff --git a/absl/strings/internal/str_format/parser.cc b/absl/strings/internal/str_format/parser.cc
index 9ef5615c..eff68f35 100644
--- a/absl/strings/internal/str_format/parser.cc
+++ b/absl/strings/internal/str_format/parser.cc
@@ -14,6 +14,7 @@
 #include <unordered_set>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 using CC = ConversionChar::Id;
@@ -300,4 +301,5 @@ bool ParsedFormatBase::MatchesConversions(
 }
 
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_format/parser.h b/absl/strings/internal/str_format/parser.h
index 4b441f71..116dda06 100644
--- a/absl/strings/internal/str_format/parser.h
+++ b/absl/strings/internal/str_format/parser.h
@@ -16,6 +16,7 @@
 #include "absl/strings/internal/str_format/extension.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 // The analyzed properties of a single specified conversion.
@@ -317,6 +318,7 @@ class ExtendedParsedFormat : public str_format_internal::ParsedFormatBase {
       : ParsedFormatBase(s, allow_ignored, {C...}) {}
 };
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
diff --git a/absl/strings/internal/str_format/parser_test.cc b/absl/strings/internal/str_format/parser_test.cc
index 6d356093..33ed8f09 100644
--- a/absl/strings/internal/str_format/parser_test.cc
+++ b/absl/strings/internal/str_format/parser_test.cc
@@ -7,6 +7,7 @@
 #include "absl/base/macros.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace str_format_internal {
 
 namespace {
@@ -389,4 +390,5 @@ TEST_F(ParsedFormatTest, ParsingFlagOrder) {
 
 }  // namespace
 }  // namespace str_format_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/str_join_internal.h b/absl/strings/internal/str_join_internal.h
index 7c35f4de..31dbf672 100644
--- a/absl/strings/internal/str_join_internal.h
+++ b/absl/strings/internal/str_join_internal.h
@@ -43,6 +43,7 @@
 #include "absl/strings/str_cat.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 //
@@ -307,6 +308,7 @@ std::string JoinRange(const Range& range, absl::string_view separator) {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_JOIN_INTERNAL_H_
diff --git a/absl/strings/internal/str_split_internal.h b/absl/strings/internal/str_split_internal.h
index 52f62226..b54f6ebe 100644
--- a/absl/strings/internal/str_split_internal.h
+++ b/absl/strings/internal/str_split_internal.h
@@ -47,6 +47,7 @@
 #endif  // _GLIBCXX_DEBUG
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // This class is implicitly constructible from everything that absl::string_view
@@ -448,6 +449,7 @@ class Splitter {
 };
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_STR_SPLIT_INTERNAL_H_
diff --git a/absl/strings/internal/utf8.cc b/absl/strings/internal/utf8.cc
index 82d36c24..8fd8edc1 100644
--- a/absl/strings/internal/utf8.cc
+++ b/absl/strings/internal/utf8.cc
@@ -17,6 +17,7 @@
 #include "absl/strings/internal/utf8.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 size_t EncodeUTF8Char(char *buffer, char32_t utf8_char) {
@@ -48,4 +49,5 @@ size_t EncodeUTF8Char(char *buffer, char32_t utf8_char) {
 }
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/internal/utf8.h b/absl/strings/internal/utf8.h
index 04236304..32fb1093 100644
--- a/absl/strings/internal/utf8.h
+++ b/absl/strings/internal/utf8.h
@@ -20,7 +20,10 @@
 #include <cstddef>
 #include <cstdint>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 // For Unicode code points 0 through 0x10FFFF, EncodeUTF8Char writes
@@ -41,6 +44,7 @@ enum { kMaxEncodedUTF8Size = 4 };
 size_t EncodeUTF8Char(char *buffer, char32_t utf8_char);
 
 }  // namespace strings_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_INTERNAL_UTF8_H_
diff --git a/absl/strings/match.cc b/absl/strings/match.cc
index 7b24241a..8127cb0c 100644
--- a/absl/strings/match.cc
+++ b/absl/strings/match.cc
@@ -17,6 +17,7 @@
 #include "absl/strings/internal/memutil.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 bool EqualsIgnoreCase(absl::string_view piece1, absl::string_view piece2) {
   return (piece1.size() == piece2.size() &&
@@ -35,4 +36,5 @@ bool EndsWithIgnoreCase(absl::string_view text, absl::string_view suffix) {
          EqualsIgnoreCase(text.substr(text.size() - suffix.size()), suffix);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/match.h b/absl/strings/match.h
index 762f359f..90fca98a 100644
--- a/absl/strings/match.h
+++ b/absl/strings/match.h
@@ -20,7 +20,7 @@
 // This file contains simple utilities for performing string matching checks.
 // All of these function parameters are specified as `absl::string_view`,
 // meaning that these functions can accept `std::string`, `absl::string_view` or
-// nul-terminated C-style strings.
+// NUL-terminated C-style strings.
 //
 // Examples:
 //   std::string s = "foo";
@@ -38,6 +38,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // StrContains()
 //
@@ -83,6 +84,7 @@ bool StartsWithIgnoreCase(absl::string_view text, absl::string_view prefix);
 // case in the comparison.
 bool EndsWithIgnoreCase(absl::string_view text, absl::string_view suffix);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_MATCH_H_
diff --git a/absl/strings/numbers.cc b/absl/strings/numbers.cc
index 4890bd54..caab4631 100644
--- a/absl/strings/numbers.cc
+++ b/absl/strings/numbers.cc
@@ -40,6 +40,7 @@
 #include "absl/strings/str_cat.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 bool SimpleAtof(absl::string_view str, float* out) {
   *out = 0.0;
@@ -911,4 +912,5 @@ bool safe_strtou128_base(absl::string_view text, uint128* value, int base) {
 }
 
 }  // namespace numbers_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/numbers.h b/absl/strings/numbers.h
index 7a0d6f50..61204683 100644
--- a/absl/strings/numbers.h
+++ b/absl/strings/numbers.h
@@ -51,6 +51,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // SimpleAtoi()
 //
@@ -95,11 +96,13 @@ ABSL_MUST_USE_RESULT bool SimpleAtod(absl::string_view str, double* out);
 // unspecified state.
 ABSL_MUST_USE_RESULT bool SimpleAtob(absl::string_view str, bool* out);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // End of public API.  Implementation details follow.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace numbers_internal {
 
 // Digit conversion.
@@ -254,6 +257,7 @@ ABSL_MUST_USE_RESULT inline bool SimpleAtoi(absl::string_view str,
   return numbers_internal::safe_strtou128_base(str, out, 10);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_NUMBERS_H_
diff --git a/absl/strings/str_cat.cc b/absl/strings/str_cat.cc
index 4bd56f5f..d9afe2f3 100644
--- a/absl/strings/str_cat.cc
+++ b/absl/strings/str_cat.cc
@@ -25,6 +25,7 @@
 #include "absl/strings/numbers.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 AlphaNum::AlphaNum(Hex hex) {
   static_assert(numbers_internal::kFastToBufferSize >= 32,
@@ -241,4 +242,5 @@ void StrAppend(std::string* dest, const AlphaNum& a, const AlphaNum& b,
   assert(out == begin + dest->size());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/str_cat.h b/absl/strings/str_cat.h
index 663a1945..292fa235 100644
--- a/absl/strings/str_cat.h
+++ b/absl/strings/str_cat.h
@@ -64,6 +64,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace strings_internal {
 // AlphaNumBuffer allows a way to pass a string to StrCat without having to do
@@ -401,6 +402,7 @@ SixDigits(double d) {
   return result;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STR_CAT_H_
diff --git a/absl/strings/str_format.h b/absl/strings/str_format.h
index c11c93a2..fbbfe43d 100644
--- a/absl/strings/str_format.h
+++ b/absl/strings/str_format.h
@@ -82,6 +82,7 @@
 #include "absl/strings/internal/str_format/parser.h"  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // UntypedFormatSpec
 //
@@ -530,6 +531,7 @@ ABSL_MUST_USE_RESULT inline bool FormatUntyped(
       str_format_internal::UntypedFormatSpecImpl::Extract(format), args);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STR_FORMAT_H_
diff --git a/absl/strings/str_format_test.cc b/absl/strings/str_format_test.cc
index cfd81bb3..d33bcaa2 100644
--- a/absl/strings/str_format_test.cc
+++ b/absl/strings/str_format_test.cc
@@ -10,6 +10,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 using str_format_internal::FormatArgImpl;
 
@@ -622,6 +623,7 @@ TEST_F(FormatWrapperTest, ParsedFormat) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // Some codegen thunks that we can use to easily dump the generated assembly for
diff --git a/absl/strings/str_join.h b/absl/strings/str_join.h
index 4772f5d1..ae5731a4 100644
--- a/absl/strings/str_join.h
+++ b/absl/strings/str_join.h
@@ -60,6 +60,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // Concept: Formatter
@@ -286,6 +287,7 @@ std::string StrJoin(const std::tuple<T...>& value,
   return strings_internal::JoinAlgorithm(value, separator, AlphaNumFormatter());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STR_JOIN_H_
diff --git a/absl/strings/str_replace.cc b/absl/strings/str_replace.cc
index 280f63d3..2bd5fa98 100644
--- a/absl/strings/str_replace.cc
+++ b/absl/strings/str_replace.cc
@@ -17,6 +17,7 @@
 #include "absl/strings/str_cat.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace strings_internal {
 
 using FixedMapping =
@@ -77,4 +78,5 @@ int StrReplaceAll(strings_internal::FixedMapping replacements,
   return StrReplaceAll<strings_internal::FixedMapping>(replacements, target);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/str_replace.h b/absl/strings/str_replace.h
index 30540d02..273c7077 100644
--- a/absl/strings/str_replace.h
+++ b/absl/strings/str_replace.h
@@ -46,6 +46,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // StrReplaceAll()
 //
@@ -212,6 +213,7 @@ int StrReplaceAll(const StrToStrMapping& replacements, std::string* target) {
   return substitutions;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STR_REPLACE_H_
diff --git a/absl/strings/str_split.cc b/absl/strings/str_split.cc
index 25931307..d0f86669 100644
--- a/absl/strings/str_split.cc
+++ b/absl/strings/str_split.cc
@@ -27,6 +27,7 @@
 #include "absl/strings/ascii.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -134,4 +135,5 @@ absl::string_view ByLength::Find(absl::string_view text,
   return absl::string_view(substr.data() + length_, 0);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/str_split.h b/absl/strings/str_split.h
index 73330789..a79cd4a0 100644
--- a/absl/strings/str_split.h
+++ b/absl/strings/str_split.h
@@ -49,6 +49,7 @@
 #include "absl/strings/strip.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 //------------------------------------------------------------------------------
 // Delimiters
@@ -506,6 +507,7 @@ StrSplit(strings_internal::ConvertibleToStringView text, Delimiter d,
       std::move(text), DelimiterType(d), std::move(p));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STR_SPLIT_H_
diff --git a/absl/strings/string_view.cc b/absl/strings/string_view.cc
index d5e1a3de..c5f5de93 100644
--- a/absl/strings/string_view.cc
+++ b/absl/strings/string_view.cc
@@ -24,6 +24,7 @@
 #include "absl/strings/internal/memutil.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 void WritePadding(std::ostream& o, size_t pad) {
@@ -228,6 +229,7 @@ constexpr string_view::size_type string_view::npos;
 ABSL_STRING_VIEW_SELECTANY
 constexpr string_view::size_type string_view::kMaxSize;
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_STRING_VIEW
diff --git a/absl/strings/string_view.h b/absl/strings/string_view.h
index 6a650874..4b34e563 100644
--- a/absl/strings/string_view.h
+++ b/absl/strings/string_view.h
@@ -35,7 +35,9 @@
 #include <string_view>  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::string_view;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_STRING_VIEW
@@ -61,6 +63,7 @@ using std::string_view;
 #include "absl/base/port.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // absl::string_view
 //
@@ -109,10 +112,10 @@ namespace absl {
 // example, when splitting a string, `std::vector<absl::string_view>` is a
 // natural data type for the output.
 //
-// When constructed from a source which is nul-terminated, the `string_view`
-// itself will not include the nul-terminator unless a specific size (including
-// the nul) is passed to the constructor. As a result, common idioms that work
-// on nul-terminated strings do not work on `string_view` objects. If you write
+// When constructed from a source which is NUL-terminated, the `string_view`
+// itself will not include the NUL-terminator unless a specific size (including
+// the NUL) is passed to the constructor. As a result, common idioms that work
+// on NUL-terminated strings do not work on `string_view` objects. If you write
 // code that scans a `string_view`, you must check its length rather than test
 // for nul, for example. Note, however, that nuls may still be embedded within
 // a `string_view` explicitly.
@@ -179,7 +182,7 @@ class string_view {
       // doesn't need to be reevaluated after `ptr_` is set.
       : string_view(str.data(), str.size()) {}
 
-  // Implicit constructor of a `string_view` from nul-terminated `str`. When
+  // Implicit constructor of a `string_view` from NUL-terminated `str`. When
   // accepting possibly null strings, use `absl::NullSafeStringView(str)`
   // instead (see below).
   constexpr string_view(const char* str)  // NOLINT(runtime/explicit)
@@ -309,8 +312,8 @@ class string_view {
   //
   // Returns a pointer to the underlying character array (which is of course
   // stored elsewhere). Note that `string_view::data()` may contain embedded nul
-  // characters, but the returned buffer may or may not be nul-terminated;
-  // therefore, do not pass `data()` to a routine that expects a nul-terminated
+  // characters, but the returned buffer may or may not be NUL-terminated;
+  // therefore, do not pass `data()` to a routine that expects a NUL-terminated
   // std::string.
   constexpr const_pointer data() const noexcept { return ptr_; }
 
@@ -577,6 +580,7 @@ constexpr bool operator>=(string_view x, string_view y) noexcept {
 // IO Insertion Operator
 std::ostream& operator<<(std::ostream& o, string_view piece);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_INTERNAL_STRING_VIEW_MEMCMP
@@ -584,6 +588,7 @@ std::ostream& operator<<(std::ostream& o, string_view piece);
 #endif  // ABSL_USES_STD_STRING_VIEW
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // ClippedSubstr()
 //
@@ -604,6 +609,7 @@ inline string_view NullSafeStringView(const char* p) {
   return p ? string_view(p) : string_view();
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STRING_VIEW_H_
diff --git a/absl/strings/strip.h b/absl/strings/strip.h
index e1341e08..111872ca 100644
--- a/absl/strings/strip.h
+++ b/absl/strings/strip.h
@@ -30,6 +30,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // ConsumePrefix()
 //
@@ -84,6 +85,7 @@ ABSL_MUST_USE_RESULT inline absl::string_view StripSuffix(
   return str;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_STRIP_H_
diff --git a/absl/strings/substitute.cc b/absl/strings/substitute.cc
index 5d28c528..5b69a3ef 100644
--- a/absl/strings/substitute.cc
+++ b/absl/strings/substitute.cc
@@ -23,6 +23,7 @@
 #include "absl/strings/string_view.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace substitute_internal {
 
 void SubstituteAndAppendArray(std::string* output, absl::string_view format,
@@ -166,4 +167,5 @@ Arg::Arg(Dec dec) {
 }
 
 }  // namespace substitute_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/strings/substitute.h b/absl/strings/substitute.h
index 233e9dcf..766aca42 100644
--- a/absl/strings/substitute.h
+++ b/absl/strings/substitute.h
@@ -86,6 +86,7 @@
 #include "absl/strings/strip.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace substitute_internal {
 
 // Arg
@@ -681,6 +682,7 @@ std::string Substitute(
                      "format std::string doesn't contain all of $0 through $9");
 #endif  // ABSL_BAD_CALL_IF
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_STRINGS_SUBSTITUTE_H_
diff --git a/absl/synchronization/BUILD.bazel b/absl/synchronization/BUILD.bazel
index 36dc98f3..3f876b9f 100644
--- a/absl/synchronization/BUILD.bazel
+++ b/absl/synchronization/BUILD.bazel
@@ -43,6 +43,7 @@ cc_library(
     deps = [
         "//absl/base",
         "//absl/base:base_internal",
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:malloc_internal",
         "//absl/base:raw_logging_internal",
diff --git a/absl/synchronization/CMakeLists.txt b/absl/synchronization/CMakeLists.txt
index 3c47a1bc..dfe5d05d 100644
--- a/absl/synchronization/CMakeLists.txt
+++ b/absl/synchronization/CMakeLists.txt
@@ -26,6 +26,7 @@ absl_cc_library(
   DEPS
     absl::base
     absl::base_internal
+    absl::config
     absl::core_headers
     absl::malloc_internal
     absl::raw_logging_internal
diff --git a/absl/synchronization/barrier.cc b/absl/synchronization/barrier.cc
index c2c539ac..0dfd795e 100644
--- a/absl/synchronization/barrier.cc
+++ b/absl/synchronization/barrier.cc
@@ -18,6 +18,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Return whether int *arg is zero.
 static bool IsZero(void *arg) {
@@ -47,4 +48,5 @@ bool Barrier::Block() {
   return this->num_to_exit_ == 0;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/barrier.h b/absl/synchronization/barrier.h
index cb5d821a..d8e75440 100644
--- a/absl/synchronization/barrier.h
+++ b/absl/synchronization/barrier.h
@@ -23,6 +23,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Barrier
 //
@@ -73,5 +74,6 @@ class Barrier {
   int num_to_exit_ ABSL_GUARDED_BY(lock_);
 };
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_SYNCHRONIZATION_BARRIER_H_
diff --git a/absl/synchronization/blocking_counter.cc b/absl/synchronization/blocking_counter.cc
index 481a06b2..3cea7aed 100644
--- a/absl/synchronization/blocking_counter.cc
+++ b/absl/synchronization/blocking_counter.cc
@@ -17,6 +17,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Return whether int *arg is zero.
 static bool IsZero(void *arg) {
@@ -52,4 +53,5 @@ void BlockingCounter::Wait() {
   // after we return from this method.
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/blocking_counter.h b/absl/synchronization/blocking_counter.h
index 77560fc0..1f53f9f2 100644
--- a/absl/synchronization/blocking_counter.h
+++ b/absl/synchronization/blocking_counter.h
@@ -24,6 +24,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // BlockingCounter
 //
@@ -92,6 +93,7 @@ class BlockingCounter {
   int num_waiting_ ABSL_GUARDED_BY(lock_);
 };
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_BLOCKING_COUNTER_H_
diff --git a/absl/synchronization/blocking_counter_test.cc b/absl/synchronization/blocking_counter_test.cc
index c63e3392..2926224a 100644
--- a/absl/synchronization/blocking_counter_test.cc
+++ b/absl/synchronization/blocking_counter_test.cc
@@ -22,6 +22,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 void PauseAndDecreaseCounter(BlockingCounter* counter, int* done) {
@@ -63,4 +64,5 @@ TEST(BlockingCounterTest, BasicFunctionality) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/create_thread_identity.cc b/absl/synchronization/internal/create_thread_identity.cc
index ec49d1ca..fa0070a9 100644
--- a/absl/synchronization/internal/create_thread_identity.cc
+++ b/absl/synchronization/internal/create_thread_identity.cc
@@ -27,6 +27,7 @@
 #include "absl/synchronization/internal/per_thread_sem.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // ThreadIdentity storage is persistent, we maintain a free-list of previously
@@ -133,6 +134,7 @@ base_internal::ThreadIdentity* CreateThreadIdentity() {
 }
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_LOW_LEVEL_ALLOC_MISSING
diff --git a/absl/synchronization/internal/create_thread_identity.h b/absl/synchronization/internal/create_thread_identity.h
index 97237a6e..e121f683 100644
--- a/absl/synchronization/internal/create_thread_identity.h
+++ b/absl/synchronization/internal/create_thread_identity.h
@@ -29,6 +29,7 @@
 #include "absl/base/port.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // Allocates and attaches a ThreadIdentity object for the calling thread.
@@ -53,6 +54,7 @@ inline base_internal::ThreadIdentity* GetOrCreateCurrentThreadIdentity() {
 }
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_CREATE_THREAD_IDENTITY_H_
diff --git a/absl/synchronization/internal/graphcycles.cc b/absl/synchronization/internal/graphcycles.cc
index 0c8c7564..6a2bcdf6 100644
--- a/absl/synchronization/internal/graphcycles.cc
+++ b/absl/synchronization/internal/graphcycles.cc
@@ -44,6 +44,7 @@
 // Do not use STL.   This module does not use standard memory allocation.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 namespace {
@@ -690,6 +691,7 @@ int GraphCycles::GetStackTrace(GraphId id, void*** ptr) {
 }
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_LOW_LEVEL_ALLOC_MISSING
diff --git a/absl/synchronization/internal/graphcycles.h b/absl/synchronization/internal/graphcycles.h
index e08dc09d..ceba33e4 100644
--- a/absl/synchronization/internal/graphcycles.h
+++ b/absl/synchronization/internal/graphcycles.h
@@ -40,7 +40,10 @@
 
 #include <cstdint>
 
+#include "absl/base/config.h"
+
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // Opaque identifier for a graph node.
@@ -132,6 +135,7 @@ class GraphCycles {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif
diff --git a/absl/synchronization/internal/graphcycles_test.cc b/absl/synchronization/internal/graphcycles_test.cc
index 58e8477b..74eaffe7 100644
--- a/absl/synchronization/internal/graphcycles_test.cc
+++ b/absl/synchronization/internal/graphcycles_test.cc
@@ -25,6 +25,7 @@
 #include "absl/base/macros.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // We emulate a GraphCycles object with a node vector and an edge vector.
@@ -459,4 +460,5 @@ TEST_F(GraphCyclesTest, ManyEdges) {
 }
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/kernel_timeout.h b/absl/synchronization/internal/kernel_timeout.h
index 61c72e75..d6ac5db0 100644
--- a/absl/synchronization/internal/kernel_timeout.h
+++ b/absl/synchronization/internal/kernel_timeout.h
@@ -34,6 +34,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 class Futex;
@@ -148,6 +149,7 @@ class KernelTimeout {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_KERNEL_TIMEOUT_H_
diff --git a/absl/synchronization/internal/mutex_nonprod.cc b/absl/synchronization/internal/mutex_nonprod.cc
index 267deaff..4590b98d 100644
--- a/absl/synchronization/internal/mutex_nonprod.cc
+++ b/absl/synchronization/internal/mutex_nonprod.cc
@@ -31,6 +31,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 namespace {
@@ -315,4 +316,5 @@ bool Condition::Eval() const {
 
 void RegisterSymbolizer(bool (*)(const void*, char*, int)) {}
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/mutex_nonprod.inc b/absl/synchronization/internal/mutex_nonprod.inc
index b8d5af79..85dae0ff 100644
--- a/absl/synchronization/internal/mutex_nonprod.inc
+++ b/absl/synchronization/internal/mutex_nonprod.inc
@@ -36,6 +36,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 class Condition;
 
 namespace synchronization_internal {
@@ -256,4 +257,5 @@ class SynchronizationStorage {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/per_thread_sem.cc b/absl/synchronization/internal/per_thread_sem.cc
index 2a78b20f..821ca9b4 100644
--- a/absl/synchronization/internal/per_thread_sem.cc
+++ b/absl/synchronization/internal/per_thread_sem.cc
@@ -25,6 +25,7 @@
 #include "absl/synchronization/internal/waiter.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 void PerThreadSem::SetThreadBlockedCounter(std::atomic<int> *counter) {
@@ -62,6 +63,7 @@ void PerThreadSem::Tick(base_internal::ThreadIdentity *identity) {
 }
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 extern "C" {
diff --git a/absl/synchronization/internal/per_thread_sem.h b/absl/synchronization/internal/per_thread_sem.h
index 113cdfb7..8ab43915 100644
--- a/absl/synchronization/internal/per_thread_sem.h
+++ b/absl/synchronization/internal/per_thread_sem.h
@@ -32,6 +32,7 @@
 #include "absl/synchronization/internal/kernel_timeout.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Mutex;
 
@@ -85,6 +86,7 @@ class PerThreadSem {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // In some build configurations we pass --detect-odr-violations to the
diff --git a/absl/synchronization/internal/per_thread_sem_test.cc b/absl/synchronization/internal/per_thread_sem_test.cc
index dba72390..b5a2f6d4 100644
--- a/absl/synchronization/internal/per_thread_sem_test.cc
+++ b/absl/synchronization/internal/per_thread_sem_test.cc
@@ -33,6 +33,7 @@
 // primitives which might use PerThreadSem, most notably absl::Mutex.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 class SimpleSemaphore {
@@ -175,4 +176,5 @@ TEST_F(PerThreadSemTest, Timeouts) {
 }  // namespace
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/thread_pool.h b/absl/synchronization/internal/thread_pool.h
index a00f2be8..0cb96dac 100644
--- a/absl/synchronization/internal/thread_pool.h
+++ b/absl/synchronization/internal/thread_pool.h
@@ -26,6 +26,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // A simple ThreadPool implementation for tests.
@@ -86,6 +87,7 @@ class ThreadPool {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_THREAD_POOL_H_
diff --git a/absl/synchronization/internal/waiter.cc b/absl/synchronization/internal/waiter.cc
index e7000d3a..ddd6081e 100644
--- a/absl/synchronization/internal/waiter.cc
+++ b/absl/synchronization/internal/waiter.cc
@@ -49,6 +49,7 @@
 #include "absl/synchronization/internal/kernel_timeout.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 static void MaybeBecomeIdle() {
@@ -481,4 +482,5 @@ void Waiter::InternalCondVarPoke() {
 #endif
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/internal/waiter.h b/absl/synchronization/internal/waiter.h
index 9540598b..5af5c282 100644
--- a/absl/synchronization/internal/waiter.h
+++ b/absl/synchronization/internal/waiter.h
@@ -62,6 +62,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace synchronization_internal {
 
 // Waiter is an OS-specific semaphore.
@@ -157,6 +158,7 @@ class Waiter {
 };
 
 }  // namespace synchronization_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_WAITER_H_
diff --git a/absl/synchronization/mutex.cc b/absl/synchronization/mutex.cc
index 100def2d..46af8a52 100644
--- a/absl/synchronization/mutex.cc
+++ b/absl/synchronization/mutex.cc
@@ -71,6 +71,7 @@ ABSL_ATTRIBUTE_WEAK void AbslInternalMutexYield() { std::this_thread::yield(); }
 }  // extern "C"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -295,7 +296,7 @@ static struct SynchEvent {     // this is a trivial hash table for the events
   bool log;             // logging turned on
 
   // Constant after initialization
-  char name[1];         // actually longer---null-terminated std::string
+  char name[1];         // actually longer---NUL-terminated std::string
 } * synch_event[kNSynchEvent] ABSL_GUARDED_BY(synch_event_mu);
 
 // Ensure that the object at "addr" has a SynchEvent struct associated with it,
@@ -2720,4 +2721,5 @@ bool Condition::GuaranteedEqual(const Condition *a, const Condition *b) {
          a->arg_ == b->arg_ && a->method_ == b->method_;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/mutex.h b/absl/synchronization/mutex.h
index ccd94618..8c70c4ce 100644
--- a/absl/synchronization/mutex.h
+++ b/absl/synchronization/mutex.h
@@ -82,6 +82,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Condition;
 struct SynchWaitParams;
@@ -1000,7 +1001,7 @@ void RegisterCondVarTracer(void (*fn)(const char *msg, const void *cv));
 //
 // 'pc' is the program counter being symbolized, 'out' is the buffer to write
 // into, and 'out_size' is the size of the buffer.  This function can return
-// false if symbolizing failed, or true if a null-terminated symbol was written
+// false if symbolizing failed, or true if a NUL-terminated symbol was written
 // to 'out.'
 //
 // This has the same memory ordering concerns as RegisterMutexProfiler() above.
@@ -1039,6 +1040,7 @@ enum class OnDeadlockCycle {
 // the manner chosen here.
 void SetMutexDeadlockDetectionMode(OnDeadlockCycle mode);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // In some build configurations we pass --detect-odr-violations to the
diff --git a/absl/synchronization/notification.cc b/absl/synchronization/notification.cc
index 1eb7f416..e91b9038 100644
--- a/absl/synchronization/notification.cc
+++ b/absl/synchronization/notification.cc
@@ -22,6 +22,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 void Notification::Notify() {
   MutexLock l(&this->mutex_);
@@ -73,4 +74,5 @@ bool Notification::WaitForNotificationWithDeadline(absl::Time deadline) const {
   return notified;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/synchronization/notification.h b/absl/synchronization/notification.h
index 36c2ce3d..9a354ca2 100644
--- a/absl/synchronization/notification.h
+++ b/absl/synchronization/notification.h
@@ -57,6 +57,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // Notification
@@ -116,6 +117,7 @@ class Notification {
   std::atomic<bool> notified_yet_;  // written under mutex_
 };
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_SYNCHRONIZATION_NOTIFICATION_H_
diff --git a/absl/synchronization/notification_test.cc b/absl/synchronization/notification_test.cc
index 059d4cd2..100ea76f 100644
--- a/absl/synchronization/notification_test.cc
+++ b/absl/synchronization/notification_test.cc
@@ -21,6 +21,7 @@
 #include "absl/synchronization/mutex.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // A thread-safe class that holds a counter.
 class ThreadSafeCounter {
@@ -128,4 +129,5 @@ TEST(NotificationTest, SanityTest) {
   BasicTests(true, &local_notification2);
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/civil_time.cc b/absl/time/civil_time.cc
index 7b86fa8b..ada82cbc 100644
--- a/absl/time/civil_time.cc
+++ b/absl/time/civil_time.cc
@@ -21,6 +21,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -170,4 +171,5 @@ std::ostream& operator<<(std::ostream& os, CivilSecond s) {
 
 }  // namespace time_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/civil_time.h b/absl/time/civil_time.h
index 77c3be2e..bb460044 100644
--- a/absl/time/civil_time.h
+++ b/absl/time/civil_time.h
@@ -76,6 +76,7 @@
 #include "absl/time/internal/cctz/include/cctz/civil_time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace time_internal {
 struct second_tag : cctz::detail::second_tag {};
@@ -531,6 +532,7 @@ std::ostream& operator<<(std::ostream& os, CivilSecond s);
 
 }  // namespace time_internal
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TIME_CIVIL_TIME_H_
diff --git a/absl/time/clock.cc b/absl/time/clock.cc
index bc6f5ccf..9e9a0386 100644
--- a/absl/time/clock.cc
+++ b/absl/time/clock.cc
@@ -34,6 +34,7 @@
 #include "absl/base/thread_annotations.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 Time Now() {
   // TODO(bww): Get a timespec instead so we don't have to divide.
   int64_t n = absl::GetCurrentTimeNanos();
@@ -43,6 +44,7 @@ Time Now() {
   }
   return time_internal::FromUnixDuration(absl::Nanoseconds(n));
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // Decide if we should use the fast GetCurrentTimeNanos() algorithm
@@ -71,9 +73,11 @@ Time Now() {
 
 #if !ABSL_USE_CYCLECLOCK_FOR_GET_CURRENT_TIME_NANOS
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 int64_t GetCurrentTimeNanos() {
   return GET_CURRENT_TIME_NANOS_FROM_SYSTEM();
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 #else  // Use the cyclecounter-based implementation below.
 
@@ -91,6 +95,7 @@ static int64_t stats_slow_paths;
 static int64_t stats_fast_slow_paths;
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 // This is a friend wrapper around UnscaledCycleClock::Now()
 // (needed to access UnscaledCycleClock).
@@ -515,10 +520,12 @@ static uint64_t UpdateLastSample(uint64_t now_cycles, uint64_t now_ns,
 
   return estimated_base_ns;
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_USE_CYCLECLOCK_FOR_GET_CURRENT_TIME_NANOS
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 // Returns the maximum duration that SleepOnce() can sleep for.
@@ -546,6 +553,7 @@ void SleepOnce(absl::Duration to_sleep) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 extern "C" {
diff --git a/absl/time/clock.h b/absl/time/clock.h
index bb52e4f6..27764a92 100644
--- a/absl/time/clock.h
+++ b/absl/time/clock.h
@@ -26,6 +26,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Now()
 //
@@ -49,6 +50,7 @@ int64_t GetCurrentTimeNanos();
 // * Returns immediately when passed a nonpositive duration.
 void SleepFor(absl::Duration duration);
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 // -----------------------------------------------------------------------------
diff --git a/absl/time/duration.cc b/absl/time/duration.cc
index f0b4631d..b1af8406 100644
--- a/absl/time/duration.cc
+++ b/absl/time/duration.cc
@@ -71,6 +71,7 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -917,4 +918,5 @@ bool ParseFlag(const std::string& text, Duration* dst, std::string* ) {
 
 std::string UnparseFlag(Duration d) { return FormatDuration(d); }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/duration_test.cc b/absl/time/duration_test.cc
index 5dce9ac8..49ebd118 100644
--- a/absl/time/duration_test.cc
+++ b/absl/time/duration_test.cc
@@ -762,11 +762,6 @@ TEST(Duration, DivisionByZero) {
   const double dbl_inf = std::numeric_limits<double>::infinity();
   const double dbl_denorm = std::numeric_limits<double>::denorm_min();
 
-  // IEEE 754 behavior
-  double z = 0.0, two = 2.0;
-  EXPECT_TRUE(std::isinf(two / z));
-  EXPECT_TRUE(std::isnan(z / z));  // We'll return inf
-
   // Operator/(Duration, double)
   EXPECT_EQ(inf, zero / 0.0);
   EXPECT_EQ(-inf, zero / -0.0);
diff --git a/absl/time/format.cc b/absl/time/format.cc
index ebe872cf..5997ef0c 100644
--- a/absl/time/format.cc
+++ b/absl/time/format.cc
@@ -22,6 +22,7 @@
 namespace cctz = absl::time_internal::cctz;
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 extern const char RFC3339_full[] = "%Y-%m-%dT%H:%M:%E*S%Ez";
 extern const char RFC3339_sec[] =  "%Y-%m-%dT%H:%M:%S%Ez";
@@ -145,4 +146,5 @@ std::string UnparseFlag(absl::Time t) {
   return absl::FormatTime(RFC3339_full, t, absl::UTCTimeZone());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/internal/get_current_time_chrono.inc b/absl/time/internal/get_current_time_chrono.inc
index 5180230d..5eeb6406 100644
--- a/absl/time/internal/get_current_time_chrono.inc
+++ b/absl/time/internal/get_current_time_chrono.inc
@@ -16,6 +16,7 @@
 #include <cstdint>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 
 static int64_t GetCurrentTimeNanosFromSystem() {
@@ -26,4 +27,5 @@ static int64_t GetCurrentTimeNanosFromSystem() {
 }
 
 }  // namespace time_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/internal/get_current_time_posix.inc b/absl/time/internal/get_current_time_posix.inc
index 65474ca6..42072000 100644
--- a/absl/time/internal/get_current_time_posix.inc
+++ b/absl/time/internal/get_current_time_posix.inc
@@ -7,6 +7,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 
 static int64_t GetCurrentTimeNanosFromSystem() {
@@ -19,4 +20,5 @@ static int64_t GetCurrentTimeNanosFromSystem() {
 }
 
 }  // namespace time_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/internal/test_util.cc b/absl/time/internal/test_util.cc
index fbddbb73..9bffe121 100644
--- a/absl/time/internal/test_util.cc
+++ b/absl/time/internal/test_util.cc
@@ -24,6 +24,7 @@
 namespace cctz = absl::time_internal::cctz;
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 
 TimeZone LoadTimeZone(const std::string& name) {
@@ -33,9 +34,11 @@ TimeZone LoadTimeZone(const std::string& name) {
 }
 
 }  // namespace time_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 namespace cctz_extension {
 namespace {
@@ -123,4 +126,5 @@ ZoneInfoSourceFactory zone_info_source_factory = TestFactory;
 
 }  // namespace cctz_extension
 }  // namespace time_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/internal/test_util.h b/absl/time/internal/test_util.h
index d7319ea8..5c4bf1f6 100644
--- a/absl/time/internal/test_util.h
+++ b/absl/time/internal/test_util.h
@@ -20,12 +20,14 @@
 #include "absl/time/time.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace time_internal {
 
 // Loads the named timezone, but dies on any failure.
 absl::TimeZone LoadTimeZone(const std::string& name);
 
 }  // namespace time_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TIME_INTERNAL_TEST_UTIL_H_
diff --git a/absl/time/time.cc b/absl/time/time.cc
index 60382be7..6bb36cb3 100644
--- a/absl/time/time.cc
+++ b/absl/time/time.cc
@@ -47,6 +47,7 @@
 namespace cctz = absl::time_internal::cctz;
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -494,4 +495,5 @@ struct tm ToTM(absl::Time t, absl::TimeZone tz) {
   return tm;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/time/time.h b/absl/time/time.h
index be064813..7507b0cd 100644
--- a/absl/time/time.h
+++ b/absl/time/time.h
@@ -89,6 +89,7 @@ struct timeval;
 #include "absl/time/internal/cctz/include/cctz/time_zone.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 class Duration;  // Defined below
 class Time;      // Defined below
@@ -1574,6 +1575,7 @@ constexpr Time FromTimeT(time_t t) {
   return time_internal::FromUnixDuration(Seconds(t));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TIME_TIME_H_
diff --git a/absl/types/any.h b/absl/types/any.h
index f7967694..16bda79c 100644
--- a/absl/types/any.h
+++ b/absl/types/any.h
@@ -61,10 +61,12 @@
 #include <any>  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::any;
 using std::any_cast;
 using std::bad_any_cast;
 using std::make_any;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_ANY
@@ -91,6 +93,7 @@ using std::make_any;
 #endif  // !defined(__GNUC__) || defined(__GXX_RTTI)
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace any_internal {
 
@@ -534,6 +537,7 @@ T* any_cast(any* operand) noexcept {
              : nullptr;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_ANY_DETAIL_HAS_RTTI
diff --git a/absl/types/bad_any_cast.cc b/absl/types/bad_any_cast.cc
index 2a538126..b0592cc9 100644
--- a/absl/types/bad_any_cast.cc
+++ b/absl/types/bad_any_cast.cc
@@ -22,6 +22,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 bad_any_cast::~bad_any_cast() = default;
 
@@ -39,6 +40,7 @@ void ThrowBadAnyCast() {
 }
 
 }  // namespace any_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_ANY
diff --git a/absl/types/bad_any_cast.h b/absl/types/bad_any_cast.h
index 6a53c010..114cef80 100644
--- a/absl/types/bad_any_cast.h
+++ b/absl/types/bad_any_cast.h
@@ -30,12 +30,15 @@
 #include <any>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::bad_any_cast;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_ANY
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // bad_any_cast
@@ -64,6 +67,7 @@ namespace any_internal {
 [[noreturn]] void ThrowBadAnyCast();
 
 }  // namespace any_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_ANY
diff --git a/absl/types/bad_optional_access.cc b/absl/types/bad_optional_access.cc
index d9ec21bf..26aca70d 100644
--- a/absl/types/bad_optional_access.cc
+++ b/absl/types/bad_optional_access.cc
@@ -22,6 +22,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 bad_optional_access::~bad_optional_access() = default;
 
@@ -41,6 +42,7 @@ void throw_bad_optional_access() {
 }
 
 }  // namespace optional_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_OPTIONAL
diff --git a/absl/types/bad_optional_access.h b/absl/types/bad_optional_access.h
index 32dd6a91..a500286a 100644
--- a/absl/types/bad_optional_access.h
+++ b/absl/types/bad_optional_access.h
@@ -30,12 +30,15 @@
 #include <optional>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::bad_optional_access;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_OPTIONAL
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // bad_optional_access
@@ -67,6 +70,7 @@ namespace optional_internal {
 [[noreturn]] void throw_bad_optional_access();
 
 }  // namespace optional_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_OPTIONAL
diff --git a/absl/types/bad_variant_access.cc b/absl/types/bad_variant_access.cc
index dbaea9e9..3dc88cc0 100644
--- a/absl/types/bad_variant_access.cc
+++ b/absl/types/bad_variant_access.cc
@@ -23,6 +23,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 //////////////////////////
 // [variant.bad.access] //
@@ -57,6 +58,7 @@ void Rethrow() {
 }
 
 }  // namespace variant_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_VARIANT
diff --git a/absl/types/bad_variant_access.h b/absl/types/bad_variant_access.h
index 6935d01b..095969f9 100644
--- a/absl/types/bad_variant_access.h
+++ b/absl/types/bad_variant_access.h
@@ -30,12 +30,15 @@
 #include <variant>
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::bad_variant_access;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_VARIANT
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // bad_variant_access
@@ -71,6 +74,7 @@ namespace variant_internal {
 [[noreturn]] void Rethrow();
 
 }  // namespace variant_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_USES_STD_VARIANT
diff --git a/absl/types/compare.h b/absl/types/compare.h
index a213e0b0..c29ced52 100644
--- a/absl/types/compare.h
+++ b/absl/types/compare.h
@@ -39,6 +39,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace compare_internal {
 
 using value_type = int8_t;
@@ -551,6 +552,7 @@ constexpr absl::weak_ordering do_three_way_comparison(const Compare &compare,
 }
 
 }  // namespace compare_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TYPES_COMPARE_H_
diff --git a/absl/types/compare_test.cc b/absl/types/compare_test.cc
index ee396fc5..955844b5 100644
--- a/absl/types/compare_test.cc
+++ b/absl/types/compare_test.cc
@@ -18,6 +18,7 @@
 #include "absl/base/casts.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 // This is necessary to avoid a bunch of lint warnings suggesting that we use
@@ -334,4 +335,5 @@ TEST(Compare, StaticAsserts) {
 #endif  // __cpp_inline_variables
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/types/internal/conformance_aliases.h b/absl/types/internal/conformance_aliases.h
index 7d5d0e09..0cc6884e 100644
--- a/absl/types/internal/conformance_aliases.h
+++ b/absl/types/internal/conformance_aliases.h
@@ -26,6 +26,7 @@
 #include "absl/types/internal/conformance_profile.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace types_internal {
 
 // Creates both a Profile and a corresponding Archetype with root name "name".
@@ -438,6 +439,7 @@ using ExpandSupportedProfiles = Receiver<
 // (potentially) non-noexcept moves.
 
 }  // namespace types_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_INTERNAL_PROFILE_AND_ARCHETYPE_ALIAS
diff --git a/absl/types/internal/conformance_archetype.h b/absl/types/internal/conformance_archetype.h
index 97ee7265..2349e0f7 100644
--- a/absl/types/internal/conformance_archetype.h
+++ b/absl/types/internal/conformance_archetype.h
@@ -43,6 +43,7 @@
 #include "absl/types/internal/conformance_profile.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace types_internal {
 
 // A minimum-conforming implementation of a type with properties specified in
@@ -961,6 +962,7 @@ struct EnabledHash {
 };
 
 }  // namespace types_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 namespace std {
diff --git a/absl/types/internal/conformance_profile.h b/absl/types/internal/conformance_profile.h
index dce3bbee..e62004fd 100644
--- a/absl/types/internal/conformance_profile.h
+++ b/absl/types/internal/conformance_profile.h
@@ -44,6 +44,7 @@
 // TODO(calabrese) Add support for extending profiles.
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace types_internal {
 
 template <class T, class /*Enabler*/ = void>
@@ -369,6 +370,7 @@ template <class T>
 struct IsProfile : IsProfileImpl<T>::type {};
 
 }  // namespace types_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TYPES_INTERNAL_CONFORMANCE_PROFILE_H_
diff --git a/absl/types/internal/optional.h b/absl/types/internal/optional.h
index d41ccc75..92932b60 100644
--- a/absl/types/internal/optional.h
+++ b/absl/types/internal/optional.h
@@ -54,6 +54,7 @@
 #endif
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // Forward declaration
 template <typename T>
@@ -387,6 +388,7 @@ struct optional_hash_base<T, decltype(std::hash<absl::remove_const_t<T> >()(
 };
 
 }  // namespace optional_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #undef ABSL_OPTIONAL_USE_INHERITING_CONSTRUCTORS
diff --git a/absl/types/internal/span.h b/absl/types/internal/span.h
index d203aad5..112612f4 100644
--- a/absl/types/internal/span.h
+++ b/absl/types/internal/span.h
@@ -26,6 +26,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace span_internal {
 // A constexpr min function
@@ -121,6 +122,7 @@ template <typename From, typename To>
 using EnableIfConvertibleTo =
     typename std::enable_if<IsConvertible<From, To>::value>::type;
 }  // namespace span_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TYPES_INTERNAL_SPAN_H_
diff --git a/absl/types/internal/variant.h b/absl/types/internal/variant.h
index 58b38592..71bd3adf 100644
--- a/absl/types/internal/variant.h
+++ b/absl/types/internal/variant.h
@@ -40,6 +40,7 @@
 #if !defined(ABSL_USES_STD_VARIANT)
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 template <class... Types>
 class variant;
@@ -1638,6 +1639,7 @@ struct VariantHashBase<Variant,
 };
 
 }  // namespace variant_internal
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // !defined(ABSL_USES_STD_VARIANT)
diff --git a/absl/types/optional.h b/absl/types/optional.h
index 14032598..2025e29f 100644
--- a/absl/types/optional.h
+++ b/absl/types/optional.h
@@ -43,11 +43,13 @@
 #include <optional>  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::bad_optional_access;
 using std::optional;
 using std::make_optional;
 using std::nullopt_t;
 using std::nullopt;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_OPTIONAL
@@ -65,6 +67,7 @@ using std::nullopt;
 #include "absl/types/internal/optional.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // nullopt_t
 //
@@ -754,6 +757,7 @@ constexpr auto operator>=(const U& v, const optional<T>& x)
   return static_cast<bool>(x) ? static_cast<bool>(v >= *x) : true;
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 namespace std {
diff --git a/absl/types/optional_exception_safety_test.cc b/absl/types/optional_exception_safety_test.cc
index 0f7fae6c..8e5fe851 100644
--- a/absl/types/optional_exception_safety_test.cc
+++ b/absl/types/optional_exception_safety_test.cc
@@ -24,6 +24,7 @@
 #include "absl/base/internal/exception_safety_testing.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 namespace {
 
@@ -285,6 +286,7 @@ TEST(OptionalExceptionSafety, NothrowMoveAssign) {
 
 }  // namespace
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // #if !defined(ABSL_USES_STD_OPTIONAL) && defined(ABSL_HAVE_EXCEPTIONS)
diff --git a/absl/types/span.h b/absl/types/span.h
index b007fc1f..3283145a 100644
--- a/absl/types/span.h
+++ b/absl/types/span.h
@@ -71,6 +71,7 @@
 #include "absl/types/internal/span.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 //------------------------------------------------------------------------------
 // Span
@@ -707,5 +708,6 @@ template <int&... ExplicitArgumentBarrier, typename T, size_t N>
 constexpr Span<const T> MakeConstSpan(const T (&array)[N]) noexcept {
   return Span<const T>(array, N);
 }
+ABSL_NAMESPACE_END
 }  // namespace absl
 #endif  // ABSL_TYPES_SPAN_H_
diff --git a/absl/types/variant.h b/absl/types/variant.h
index f3558703..776d19a1 100644
--- a/absl/types/variant.h
+++ b/absl/types/variant.h
@@ -50,6 +50,7 @@
 #include <variant>  // IWYU pragma: export
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 using std::bad_variant_access;
 using std::get;
 using std::get_if;
@@ -62,6 +63,7 @@ using std::variant_npos;
 using std::variant_size;
 using std::variant_size_v;
 using std::visit;
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else  // ABSL_USES_STD_VARIANT
@@ -77,6 +79,7 @@ using std::visit;
 #include "absl/types/internal/variant.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // -----------------------------------------------------------------------------
 // absl::variant
@@ -795,6 +798,7 @@ operator>=(const variant<Types...>& a, const variant<Types...>& b) {
                    a.index());
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 namespace std {
@@ -815,6 +819,7 @@ struct hash<absl::variant<T...>>
 #endif  // ABSL_USES_STD_VARIANT
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace variant_internal {
 
 // Helper visitor for converting a variant<Ts...>` into another type (mostly
@@ -850,6 +855,7 @@ To ConvertVariantTo(Variant&& variant) {
                      std::forward<Variant>(variant));
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_TYPES_VARIANT_H_
diff --git a/absl/types/variant_benchmark.cc b/absl/types/variant_benchmark.cc
index a5f52164..350b1753 100644
--- a/absl/types/variant_benchmark.cc
+++ b/absl/types/variant_benchmark.cc
@@ -28,6 +28,7 @@
 #include "absl/utility/utility.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 template <std::size_t I>
@@ -217,4 +218,5 @@ BENCHMARK_TEMPLATE(BM_RedundantVisit, 4, 2)
     ->DenseRange(0, integral_pow(4, 2) - 1);
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/types/variant_exception_safety_test.cc b/absl/types/variant_exception_safety_test.cc
index b486a71e..439c6e1d 100644
--- a/absl/types/variant_exception_safety_test.cc
+++ b/absl/types/variant_exception_safety_test.cc
@@ -34,6 +34,7 @@
 #if !defined(ABSL_INTERNAL_MSVC_2017_DBG_MODE)
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 using ::testing::MakeExceptionSafetyTester;
@@ -523,6 +524,7 @@ TEST(VariantExceptionSafetyTest, Swap) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // !defined(ABSL_INTERNAL_MSVC_2017_DBG_MODE)
diff --git a/absl/types/variant_test.cc b/absl/types/variant_test.cc
index 2913775a..96393333 100644
--- a/absl/types/variant_test.cc
+++ b/absl/types/variant_test.cc
@@ -70,6 +70,7 @@ struct hash<Hashable> {
 struct NonHashable {};
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 namespace {
 
 using ::testing::DoubleEq;
@@ -2709,6 +2710,7 @@ TEST(VariantTest, MoveCtorBug) {
 }
 
 }  // namespace
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // #if !defined(ABSL_USES_STD_VARIANT)
diff --git a/absl/utility/utility.h b/absl/utility/utility.h
index 5a98c2c3..e6647c7b 100644
--- a/absl/utility/utility.h
+++ b/absl/utility/utility.h
@@ -51,6 +51,7 @@
 #include "absl/meta/type_traits.h"
 
 namespace absl {
+ABSL_NAMESPACE_BEGIN
 
 // integer_sequence
 //
@@ -343,6 +344,7 @@ constexpr T make_from_tuple(Tuple&& tup) {
           std::tuple_size<absl::decay_t<Tuple>>::value>{});
 }
 
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_UTILITY_UTILITY_H_
-- 
cgit v1.2.3


From e7ca23acac146b10edc4f752edd0bd28b0f14ea3 Mon Sep 17 00:00:00 2001
From: Abseil Team <absl-team@google.com>
Date: Wed, 23 Dec 2020 12:59:21 -0800
Subject: Export of internal Abseil changes

--
7c15492a46380679651a4291bb284980901d04b1 by Andy Getzendanner <durandal@google.com>:

Add some internal hooks for ABSL_RAW_LOG and do a bit of tidying up.

PiperOrigin-RevId: 348836291

--
9a438cdcf2bd8d2b7ab27f4955432abf0d087672 by Evan Brown <ezb@google.com>:

Fix a bug affecting b-tree extract() when there are multiple keys in the container that are equivalent to the lookup key.

In that case, we are supposed to extract the first such key in the container - [reference](https://en.cppreference.com/w/cpp/container/multiset/extract), but we were extracting the first one we found (which was not necessarily the first in the container).

Also, optimize internal_lower_bound to not keep searching all the way to the leaf if it finds an equivalent key on an internal node and we can't have multiple equivalent keys for the lookup key.

PiperOrigin-RevId: 348822858

--
b5e34c3af3f52815dbca3c6858c26fa8f385a408 by Abseil Team <absl-team@google.com>:

Fix misleading comment.
Ignored object can be either deallocated or leaked.

PiperOrigin-RevId: 348705960

--
64fd9e8c0684bfe86f50161b0e0e9077bb96e05c by Christian Blichmann <cblichmann@google.com>:

Minor cleanups:

- Sorting using declarations
- Changing the format of a NOLINT statement

PiperOrigin-RevId: 348641845
GitOrigin-RevId: 7c15492a46380679651a4291bb284980901d04b1
Change-Id: Ia1ccd844586bd3dced2466651f1175d40caf3d7a
---
 absl/base/internal/raw_logging.cc         | 66 ++++++++++++++++---------------
 absl/base/internal/raw_logging.h          |  8 ++++
 absl/container/btree_test.cc              | 48 +++++++++++++++++++++-
 absl/container/internal/btree.h           | 39 +++++++++++++-----
 absl/container/internal/btree_container.h | 17 ++++----
 absl/debugging/leak_check.h               |  3 +-
 absl/strings/numbers.h                    |  8 ----
 absl/strings/numbers_test.cc              |  4 +-
 8 files changed, 129 insertions(+), 64 deletions(-)

(limited to 'absl/debugging/leak_check.h')

diff --git a/absl/base/internal/raw_logging.cc b/absl/base/internal/raw_logging.cc
index ae8754c6..bdfb74b8 100644
--- a/absl/base/internal/raw_logging.cc
+++ b/absl/base/internal/raw_logging.cc
@@ -67,28 +67,32 @@
 #undef ABSL_HAVE_RAW_IO
 #endif
 
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace raw_logging_internal {
+namespace {
+
 // TODO(gfalcon): We want raw-logging to work on as many platforms as possible.
-// Explicitly #error out when not ABSL_LOW_LEVEL_WRITE_SUPPORTED, except for a
-// selected set of platforms for which we expect not to be able to raw log.
+// Explicitly `#error` out when not `ABSL_LOW_LEVEL_WRITE_SUPPORTED`, except for
+// a selected set of platforms for which we expect not to be able to raw log.
 
-ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
-    absl::raw_logging_internal::LogPrefixHook>
-    log_prefix_hook;
-ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
-    absl::raw_logging_internal::AbortHook>
-    abort_hook;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL
+    absl::base_internal::AtomicHook<LogPrefixHook>
+        log_prefix_hook;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL
+    absl::base_internal::AtomicHook<AbortHook>
+        abort_hook;
 
 #ifdef ABSL_LOW_LEVEL_WRITE_SUPPORTED
-static const char kTruncated[] = " ... (message truncated)\n";
+constexpr char kTruncated[] = " ... (message truncated)\n";
 
 // sprintf the format to the buffer, adjusting *buf and *size to reflect the
 // consumed bytes, and return whether the message fit without truncation.  If
 // truncation occurred, if possible leave room in the buffer for the message
 // kTruncated[].
-inline static bool VADoRawLog(char** buf, int* size, const char* format,
-                              va_list ap) ABSL_PRINTF_ATTRIBUTE(3, 0);
-inline static bool VADoRawLog(char** buf, int* size,
-                              const char* format, va_list ap) {
+bool VADoRawLog(char** buf, int* size, const char* format, va_list ap)
+    ABSL_PRINTF_ATTRIBUTE(3, 0);
+bool VADoRawLog(char** buf, int* size, const char* format, va_list ap) {
   int n = vsnprintf(*buf, *size, format, ap);
   bool result = true;
   if (n < 0 || n > *size) {
@@ -96,7 +100,7 @@ inline static bool VADoRawLog(char** buf, int* size,
     if (static_cast<size_t>(*size) > sizeof(kTruncated)) {
       n = *size - sizeof(kTruncated);  // room for truncation message
     } else {
-      n = 0;                           // no room for truncation message
+      n = 0;  // no room for truncation message
     }
   }
   *size -= n;
@@ -105,9 +109,7 @@ inline static bool VADoRawLog(char** buf, int* size,
 }
 #endif  // ABSL_LOW_LEVEL_WRITE_SUPPORTED
 
-static constexpr int kLogBufSize = 3000;
-
-namespace {
+constexpr int kLogBufSize = 3000;
 
 // CAVEAT: vsnprintf called from *DoRawLog below has some (exotic) code paths
 // that invoke malloc() and getenv() that might acquire some locks.
@@ -166,7 +168,7 @@ void RawLogVA(absl::LogSeverity severity, const char* file, int line,
     } else {
       DoRawLog(&buf, &size, "%s", kTruncated);
     }
-    absl::raw_logging_internal::SafeWriteToStderr(buffer, strlen(buffer));
+    SafeWriteToStderr(buffer, strlen(buffer));
   }
 #else
   static_cast<void>(format);
@@ -181,11 +183,18 @@ void RawLogVA(absl::LogSeverity severity, const char* file, int line,
   }
 }
 
+// Non-formatting version of RawLog().
+//
+// TODO(gfalcon): When string_view no longer depends on base, change this
+// interface to take its message as a string_view instead.
+void DefaultInternalLog(absl::LogSeverity severity, const char* file, int line,
+                        const std::string& message) {
+  RawLog(severity, file, line, "%.*s", static_cast<int>(message.size()),
+         message.data());
+}
+
 }  // namespace
 
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace raw_logging_internal {
 void SafeWriteToStderr(const char *s, size_t len) {
 #if defined(ABSL_HAVE_SYSCALL_WRITE)
   syscall(SYS_write, STDERR_FILENO, s, len);
@@ -200,8 +209,6 @@ void SafeWriteToStderr(const char *s, size_t len) {
 #endif
 }
 
-void RawLog(absl::LogSeverity severity, const char* file, int line,
-            const char* format, ...) ABSL_PRINTF_ATTRIBUTE(4, 5);
 void RawLog(absl::LogSeverity severity, const char* file, int line,
             const char* format, ...) {
   va_list ap;
@@ -210,15 +217,6 @@ void RawLog(absl::LogSeverity severity, const char* file, int line,
   va_end(ap);
 }
 
-// Non-formatting version of RawLog().
-//
-// TODO(gfalcon): When string_view no longer depends on base, change this
-// interface to take its message as a string_view instead.
-static void DefaultInternalLog(absl::LogSeverity severity, const char* file,
-                               int line, const std::string& message) {
-  RawLog(severity, file, line, "%s", message.c_str());
-}
-
 bool RawLoggingFullySupported() {
 #ifdef ABSL_LOW_LEVEL_WRITE_SUPPORTED
   return true;
@@ -231,6 +229,10 @@ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL
     absl::base_internal::AtomicHook<InternalLogFunction>
         internal_log_function(DefaultInternalLog);
 
+void RegisterLogPrefixHook(LogPrefixHook func) { log_prefix_hook.Store(func); }
+
+void RegisterAbortHook(AbortHook func) { abort_hook.Store(func); }
+
 void RegisterInternalLogFunction(InternalLogFunction func) {
   internal_log_function.Store(func);
 }
diff --git a/absl/base/internal/raw_logging.h b/absl/base/internal/raw_logging.h
index 20f4291b..2bf7aaba 100644
--- a/absl/base/internal/raw_logging.h
+++ b/absl/base/internal/raw_logging.h
@@ -178,6 +178,14 @@ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL extern base_internal::AtomicHook<
     InternalLogFunction>
     internal_log_function;
 
+// Registers hooks of the above types.  Only a single hook of each type may be
+// registered.  It is an error to call these functions multiple times with
+// different input arguments.
+//
+// These functions are safe to call at any point during initialization; they do
+// not block or malloc, and are async-signal safe.
+void RegisterLogPrefixHook(LogPrefixHook func);
+void RegisterAbortHook(AbortHook func);
 void RegisterInternalLogFunction(InternalLogFunction func);
 
 }  // namespace raw_logging_internal
diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index a933386a..367d75be 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -2038,6 +2038,30 @@ TEST(Btree, ExtractAndInsertNodeHandleMultiMap) {
   EXPECT_EQ(res, ++other.begin());
 }
 
+TEST(Btree, ExtractMultiMapEquivalentKeys) {
+  // Note: using string keys means a three-way comparator.
+  absl::btree_multimap<std::string, int> map;
+  for (int i = 0; i < 100; ++i) {
+    for (int j = 0; j < 100; ++j) {
+      map.insert({absl::StrCat(i), j});
+    }
+  }
+
+  for (int i = 0; i < 100; ++i) {
+    const std::string key = absl::StrCat(i);
+    auto node_handle = map.extract(key);
+    EXPECT_EQ(node_handle.key(), key);
+    EXPECT_EQ(node_handle.mapped(), 0) << i;
+  }
+
+  for (int i = 0; i < 100; ++i) {
+    const std::string key = absl::StrCat(i);
+    auto node_handle = map.extract(key);
+    EXPECT_EQ(node_handle.key(), key);
+    EXPECT_EQ(node_handle.mapped(), 1) << i;
+  }
+}
+
 // For multisets, insert with hint also affects correctness because we need to
 // insert immediately before the hint if possible.
 struct InsertMultiHintData {
@@ -2726,7 +2750,6 @@ TYPED_TEST_SUITE(BtreeMultiKeyTest, MultiKeyComps);
 
 TYPED_TEST(BtreeMultiKeyTest, EqualRange) {
   absl::btree_set<MultiKey, TypeParam> set;
-
   for (int i = 0; i < 100; ++i) {
     for (int j = 0; j < 100; ++j) {
       set.insert({i, j});
@@ -2736,11 +2759,32 @@ TYPED_TEST(BtreeMultiKeyTest, EqualRange) {
   for (int i = 0; i < 100; ++i) {
     auto equal_range = set.equal_range(i);
     EXPECT_EQ(equal_range.first->i1, i);
-    EXPECT_EQ(equal_range.first->i2, 0);
+    EXPECT_EQ(equal_range.first->i2, 0) << i;
     EXPECT_EQ(std::distance(equal_range.first, equal_range.second), 100) << i;
   }
 }
 
+TYPED_TEST(BtreeMultiKeyTest, Extract) {
+  absl::btree_set<MultiKey, TypeParam> set;
+  for (int i = 0; i < 100; ++i) {
+    for (int j = 0; j < 100; ++j) {
+      set.insert({i, j});
+    }
+  }
+
+  for (int i = 0; i < 100; ++i) {
+    auto node_handle = set.extract(i);
+    EXPECT_EQ(node_handle.value().i1, i);
+    EXPECT_EQ(node_handle.value().i2, 0) << i;
+  }
+
+  for (int i = 0; i < 100; ++i) {
+    auto node_handle = set.extract(i);
+    EXPECT_EQ(node_handle.value().i1, i);
+    EXPECT_EQ(node_handle.value().i2, 1) << i;
+  }
+}
+
 TYPED_TEST(BtreeMultiKeyTest, Erase) {
   absl::btree_set<MultiKey, TypeParam> set = {
       {1, 1}, {2, 1}, {2, 2}, {3, 1}};
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h
index d863cb30..6f5f01b8 100644
--- a/absl/container/internal/btree.h
+++ b/absl/container/internal/btree.h
@@ -1211,7 +1211,7 @@ class btree {
     return const_reverse_iterator(begin());
   }
 
-  // Finds the first element whose key is not less than key.
+  // Finds the first element whose key is not less than `key`.
   template <typename K>
   iterator lower_bound(const K &key) {
     return internal_end(internal_lower_bound(key).value);
@@ -1221,7 +1221,12 @@ class btree {
     return internal_end(internal_lower_bound(key).value);
   }
 
-  // Finds the first element whose key is greater than key.
+  // Finds the first element whose key is not less than `key` and also returns
+  // whether that element is equal to `key`.
+  template <typename K>
+  std::pair<iterator, bool> lower_bound_equal(const K &key) const;
+
+  // Finds the first element whose key is greater than `key`.
   template <typename K>
   iterator upper_bound(const K &key) {
     return internal_end(internal_upper_bound(key));
@@ -1303,8 +1308,8 @@ class btree {
   // to the element after the last erased element.
   std::pair<size_type, iterator> erase_range(iterator begin, iterator end);
 
-  // Finds the iterator corresponding to a key or returns end() if the key is
-  // not present.
+  // Finds an element with key equivalent to `key` or returns `end()` if `key`
+  // is not present.
   template <typename K>
   iterator find(const K &key) {
     return internal_end(internal_find(key));
@@ -1905,12 +1910,23 @@ constexpr bool btree<P>::static_assert_validation() {
 
 template <typename P>
 template <typename K>
-auto btree<P>::equal_range(const K &key) -> std::pair<iterator, iterator> {
+auto btree<P>::lower_bound_equal(const K &key) const
+    -> std::pair<iterator, bool> {
   const SearchResult<iterator, is_key_compare_to::value> res =
       internal_lower_bound(key);
-  const iterator lower = internal_end(res.value);
-  if (res.HasMatch() ? !res.IsEq()
-                     : lower == end() || compare_keys(key, lower.key())) {
+  const iterator lower = iterator(internal_end(res.value));
+  const bool equal = res.HasMatch()
+                         ? res.IsEq()
+                         : lower != end() && !compare_keys(key, lower.key());
+  return {lower, equal};
+}
+
+template <typename P>
+template <typename K>
+auto btree<P>::equal_range(const K &key) -> std::pair<iterator, iterator> {
+  const std::pair<iterator, bool> lower_and_equal = lower_bound_equal(key);
+  const iterator lower = lower_and_equal.first;
+  if (!lower_and_equal.second) {
     return {lower, lower};
   }
 
@@ -2510,14 +2526,17 @@ template <typename P>
 template <typename K>
 auto btree<P>::internal_lower_bound(const K &key) const
     -> SearchResult<iterator, is_key_compare_to::value> {
+  if (!params_type::template can_have_multiple_equivalent_keys<K>()) {
+    SearchResult<iterator, is_key_compare_to::value> ret = internal_locate(key);
+    ret.value = internal_last(ret.value);
+    return ret;
+  }
   iterator iter(const_cast<node_type *>(root()));
   SearchResult<int, is_key_compare_to::value> res;
   bool seen_eq = false;
   for (;;) {
     res = iter.node->lower_bound(key, key_comp());
     iter.position = res.value;
-    // TODO(ezb): we should be able to terminate early on IsEq() if there can't
-    // be multiple equivalent keys in container for this lookup type.
     if (iter.node->leaf()) {
       break;
     }
diff --git a/absl/container/internal/btree_container.h b/absl/container/internal/btree_container.h
index 887eda41..03be708e 100644
--- a/absl/container/internal/btree_container.h
+++ b/absl/container/internal/btree_container.h
@@ -338,13 +338,12 @@ class btree_set_container : public btree_container<Tree> {
   }
 
   // Node extraction routines.
-  // TODO(ezb): when the comparator is heterogeneous and has different
-  // equivalence classes for different lookup types, we should extract the first
-  // equivalent value if there are multiple.
   template <typename K = key_type>
   node_type extract(const key_arg<K> &key) {
-    auto it = this->find(key);
-    return it == this->end() ? node_type() : extract(it);
+    const std::pair<iterator, bool> lower_and_equal =
+        this->tree_.lower_bound_equal(key);
+    return lower_and_equal.second ? extract(lower_and_equal.first)
+                                  : node_type();
   }
   using super_type::extract;
 
@@ -621,12 +620,12 @@ class btree_multiset_container : public btree_container<Tree> {
   }
 
   // Node extraction routines.
-  // TODO(ezb): we are supposed to extract the first equivalent key if there are
-  // multiple, but this isn't guaranteed to extract the first one.
   template <typename K = key_type>
   node_type extract(const key_arg<K> &key) {
-    auto it = this->find(key);
-    return it == this->end() ? node_type() : extract(it);
+    const std::pair<iterator, bool> lower_and_equal =
+        this->tree_.lower_bound_equal(key);
+    return lower_and_equal.second ? extract(lower_and_equal.first)
+                                  : node_type();
   }
   using super_type::extract;
 
diff --git a/absl/debugging/leak_check.h b/absl/debugging/leak_check.h
index 7a5a22dd..b66a81c3 100644
--- a/absl/debugging/leak_check.h
+++ b/absl/debugging/leak_check.h
@@ -62,7 +62,8 @@ void DoIgnoreLeak(const void* ptr);
 //
 // If the passed `ptr` does not point to an actively allocated object at the
 // time `IgnoreLeak()` is called, the call is a no-op; if it is actively
-// allocated, the object must not get deallocated later.
+// allocated, leak sanitizer will assume this object is referenced even if
+// there is no actual reference in user memory.
 //
 template <typename T>
 T* IgnoreLeak(T* ptr) {
diff --git a/absl/strings/numbers.h b/absl/strings/numbers.h
index 7966e250..ffc738fa 100644
--- a/absl/strings/numbers.h
+++ b/absl/strings/numbers.h
@@ -1,4 +1,3 @@
-//
 // Copyright 2017 The Abseil Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -245,13 +244,6 @@ inline size_t FastHexToBufferZeroPad16(uint64_t val, char* out) {
 
 }  // namespace numbers_internal
 
-// SimpleAtoi()
-//
-// Converts a string to an integer, using `safe_strto?()` functions for actual
-// parsing, returning `true` if successful. The `safe_strto?()` functions apply
-// strict checking; the string must be a base-10 integer, optionally followed or
-// preceded by ASCII whitespace, with a value in the range of the corresponding
-// integer type.
 template <typename int_type>
 ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out) {
   return numbers_internal::safe_strtoi_base(str, out, 10);
diff --git a/absl/strings/numbers_test.cc b/absl/strings/numbers_test.cc
index 4ab67fb6..27616bf8 100644
--- a/absl/strings/numbers_test.cc
+++ b/absl/strings/numbers_test.cc
@@ -46,6 +46,7 @@
 
 namespace {
 
+using absl::SimpleAtoi;
 using absl::numbers_internal::kSixDigitsToBufferSize;
 using absl::numbers_internal::safe_strto32_base;
 using absl::numbers_internal::safe_strto64_base;
@@ -55,7 +56,6 @@ using absl::numbers_internal::SixDigitsToBuffer;
 using absl::strings_internal::Itoa;
 using absl::strings_internal::strtouint32_test_cases;
 using absl::strings_internal::strtouint64_test_cases;
-using absl::SimpleAtoi;
 using testing::Eq;
 using testing::MatchesRegex;
 
@@ -380,7 +380,7 @@ TEST(NumbersTest, Atoi) {
   VerifySimpleAtoiGood<uint32_t>(42, 42);
   VerifySimpleAtoiGood<unsigned int>(42, 42);
   VerifySimpleAtoiGood<int64_t>(-42, -42);
-  VerifySimpleAtoiGood<long>(-42, -42);  // NOLINT(runtime/int)
+  VerifySimpleAtoiGood<long>(-42, -42);  // NOLINT: runtime-int
   VerifySimpleAtoiGood<uint64_t>(42, 42);
   VerifySimpleAtoiGood<size_t>(42, 42);
   VerifySimpleAtoiGood<std::string::size_type>(42, 42);
-- 
cgit v1.2.3


From dcf4899377ca63246efb17f5468c40913855777c Mon Sep 17 00:00:00 2001
From: Abseil Team <absl-team@google.com>
Date: Wed, 17 Mar 2021 20:08:11 -0700
Subject: Export of internal Abseil changes

--
8e75347c10d85112296811be6ef35761744ad9bc by Derek Mauro <dmauro@google.com>:

Big update to LTS release process
  * Add create_lts.py script to to the LTS modification
    This is simpler than copybara since very few changes are needed
  * Use the default installation paths instead of a versioned path.
    If a versioned path is needed, this is easy to change on the commandline.
  * Make the integration test use the LTS transformed version
  * Test both static and dynamic linking (fixes pkg-config dynamic linking)

PiperOrigin-RevId: 363566934

--
e00e971a2de3138861f5e1900201c9cc7788f714 by Laramie Leavitt <lar@google.com>:

Add a non-compile test to absl::BitGenRef for temporaries.

PiperOrigin-RevId: 363437284

--
3685644ec115d99789de32aceb76c32a00756fea by Derek Mauro <dmauro@google.com>:

Make OSS code consistent with internal code by using the forward
declaration of absl::Status that contains ABSL_MUST_USE_RESULT.

PiperOrigin-RevId: 363426906

--
b85fec142c3aa3f632fa985f9f8f73a253819723 by Evan Brown <ezb@google.com>:

Move raw_hash_set::infoz_ into raw_hash_set::settings_. This reduces the size of raw_hash_sets by alignof(size_t) bytes when hashtablez is disabled.

PiperOrigin-RevId: 363034264

--
c6fde3b17e5845191eb8b2bfc1760c8bfb9573ff by Mark Barolak <mbar@google.com>:

Internal change

PiperOrigin-RevId: 362990378

--
81713cf964905b43d1cbe32ce5fed97539029625 by Abseil Team <absl-team@google.com>:

Fix typo in comment (execeptions -> exceptions).

PiperOrigin-RevId: 362946191

--
3ee92ca470feca44da417b03ee45a915c6eb5155 by Abseil Team <absl-team@google.com>:

Add absl::FindAndReportLeaks and routes it to the corresponding
__lsan_do_recoverable_leak_check.

PiperOrigin-RevId: 362622199

--
b95b7194b20e02c20d72289fbc79a0d35b82e256 by Abseil Team <absl-team@google.com>:

Add `kWithEverything` to StatusToStringMode

PiperOrigin-RevId: 362595218

--
0a960d96a0014eab7e1c55b479269450ed8e98d7 by Abseil Team <absl-team@google.com>:

Accept e.g. ".__uniq" as a valid clone name.  Further, bring the implementation
on par with libiberty's demangler grammar.

Clang introduced option -funique-internal-linkage-names that adds the suffix
".__uniq.[0-9]+" to internal linkage functions to give them a globally unique
identifier.  The suffix was designed to work with existing demanglers which do
recognize a "_" along with the alphanumeric string. This change enhances the
demangler to allow "_" with the alphanumeric string.

Please refer to libiberty's cp-demangle.c where function d_clone_suffix
implements the demangling of clone suffixes :

1.  '_' is accepted as a valid character with the alphanumeric sequence.
2.  The alphanumberic sequence is optional.
3.  The digit sequence is optional.

PiperOrigin-RevId: 362557420

--
2ac5ea212c150afd2f58025a5cab8c45d16949c6 by Abseil Team <absl-team@google.com>:

Change variable name 'slots' to 'slot_count' to avoid name-clash with Qt builds.

PiperOrigin-RevId: 362556289

--
934f0f409c9c548716a46363d6e243406fad4028 by Mark Barolak <mbar@google.com>:

Clarify the comment on ABSL_CACHELINE_SIZE to indicate that the macro definition itself shouldn't change, but rather that call sites should change when possible.

This addresses the request for improved documentation in https://github.com/abseil/abseil-cpp/pull/842.

PiperOrigin-RevId: 362354288
GitOrigin-RevId: 8e75347c10d85112296811be6ef35761744ad9bc
Change-Id: I33ec8561d8d645c3353e9d2dd447501d0e1825a7
---
 CMake/AbseilDll.cmake                        |   9 +-
 CMake/AbseilHelpers.cmake                    |  22 +++--
 CMake/AbseilInstallDirs.cmake                |  20 ----
 CMake/install_test_project/test.sh           | 138 +++++++--------------------
 CMakeLists.txt                               |  14 +--
 absl/base/optimization.h                     |   5 +-
 absl/container/internal/btree.h              |   8 +-
 absl/container/internal/raw_hash_set.h       |  57 +++++------
 absl/container/internal/raw_hash_set_test.cc |  39 +++++---
 absl/debugging/internal/demangle.cc          |  28 +++---
 absl/debugging/internal/demangle_test.cc     |  30 +++++-
 absl/debugging/leak_check.cc                 |   1 +
 absl/debugging/leak_check.h                  |  13 +++
 absl/status/internal/status_internal.h       |  11 +++
 absl/status/status.h                         |   9 +-
 absl/status/status_test.cc                   |   4 +
 absl/status/statusor.h                       |   2 +-
 absl/strings/numbers.h                       |   1 +
 ci/cmake_install_test.sh                     |  18 ++--
 create_lts.py                                | 121 +++++++++++++++++++++++
 20 files changed, 339 insertions(+), 211 deletions(-)
 delete mode 100644 CMake/AbseilInstallDirs.cmake
 create mode 100755 create_lts.py

(limited to 'absl/debugging/leak_check.h')

diff --git a/CMake/AbseilDll.cmake b/CMake/AbseilDll.cmake
index 39f85f2f..253c73ff 100644
--- a/CMake/AbseilDll.cmake
+++ b/CMake/AbseilDll.cmake
@@ -1,4 +1,5 @@
 include(CMakeParseArguments)
+include(GNUInstallDirs)
 
 set(ABSL_INTERNAL_DLL_FILES
   "algorithm/algorithm.h"
@@ -500,7 +501,7 @@ function(absl_make_dll)
     abseil_dll
     PUBLIC
       "$<BUILD_INTERFACE:${ABSL_COMMON_INCLUDE_DIRS}>"
-      $<INSTALL_INTERFACE:${ABSL_INSTALL_INCLUDEDIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
   )
 
   target_compile_options(
@@ -518,8 +519,8 @@ function(absl_make_dll)
       ${ABSL_CC_LIB_DEFINES}
   )
   install(TARGETS abseil_dll EXPORT ${PROJECT_NAME}Targets
-        RUNTIME DESTINATION ${ABSL_INSTALL_BINDIR}
-        LIBRARY DESTINATION ${ABSL_INSTALL_LIBDIR}
-        ARCHIVE DESTINATION ${ABSL_INSTALL_LIBDIR}
+        RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
   )
 endfunction()
diff --git a/CMake/AbseilHelpers.cmake b/CMake/AbseilHelpers.cmake
index 1541435d..4f6394ab 100644
--- a/CMake/AbseilHelpers.cmake
+++ b/CMake/AbseilHelpers.cmake
@@ -17,7 +17,6 @@
 include(CMakeParseArguments)
 include(AbseilConfigureCopts)
 include(AbseilDll)
-include(AbseilInstallDirs)
 
 # The IDE folder for Abseil that will be used if Abseil is included in a CMake
 # project that sets
@@ -151,6 +150,10 @@ function(absl_cc_library)
       endif()
       foreach(dep ${ABSL_CC_LIB_DEPS})
         if(${dep} MATCHES "^absl::(.*)")
+	  # Join deps with commas.
+          if(PC_DEPS)
+            set(PC_DEPS "${PC_DEPS},")
+          endif()
           set(PC_DEPS "${PC_DEPS} absl_${CMAKE_MATCH_1} = ${PC_VERSION}")
         endif()
       endforeach()
@@ -167,14 +170,14 @@ function(absl_cc_library)
       FILE(GENERATE OUTPUT "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc" CONTENT "\
 prefix=${CMAKE_INSTALL_PREFIX}\n\
 exec_prefix=\${prefix}\n\
-libdir=\${prefix}/lib\n\
-includedir=\${prefix}/include\n\
+libdir=\${prefix}/${CMAKE_INSTALL_LIBDIR}\n\
+includedir=\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}\n\
 \n\
 Name: absl_${_NAME}\n\
 Description: Abseil ${_NAME} library\n\
 URL: https://abseil.io/\n\
 Version: ${PC_VERSION}\n\
-Requires.private:${PC_DEPS}\n\
+Requires:${PC_DEPS}\n\
 Libs: -L\${libdir} $<JOIN:${ABSL_CC_LIB_LINKOPTS}, > $<$<NOT:$<BOOL:${ABSL_CC_LIB_IS_INTERFACE}>>:-labsl_${_NAME}>\n\
 Cflags: -I\${includedir}${PC_CFLAGS}\n")
       INSTALL(FILES "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc"
@@ -235,7 +238,7 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
     target_include_directories(${_NAME}
       PUBLIC
         "$<BUILD_INTERFACE:${ABSL_COMMON_INCLUDE_DIRS}>"
-        $<INSTALL_INTERFACE:${ABSL_INSTALL_INCLUDEDIR}>
+        $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
     )
     target_compile_options(${_NAME}
       PRIVATE ${ABSL_CC_LIB_COPTS})
@@ -260,7 +263,6 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
     if(ABSL_ENABLE_INSTALL)
       set_target_properties(${_NAME} PROPERTIES
         OUTPUT_NAME "absl_${_NAME}"
-        # TODO(b/173696973): Figure out how to set SOVERSION for LTS releases.
         SOVERSION 0
       )
     endif()
@@ -270,7 +272,7 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
     target_include_directories(${_NAME}
       INTERFACE
         "$<BUILD_INTERFACE:${ABSL_COMMON_INCLUDE_DIRS}>"
-        $<INSTALL_INTERFACE:${ABSL_INSTALL_INCLUDEDIR}>
+        $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
       )
 
     if (_build_type STREQUAL "dll")
@@ -290,9 +292,9 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
   # installed abseil can't be tested.
   if(NOT ABSL_CC_LIB_TESTONLY AND ABSL_ENABLE_INSTALL)
     install(TARGETS ${_NAME} EXPORT ${PROJECT_NAME}Targets
-          RUNTIME DESTINATION ${ABSL_INSTALL_BINDIR}
-          LIBRARY DESTINATION ${ABSL_INSTALL_LIBDIR}
-          ARCHIVE DESTINATION ${ABSL_INSTALL_LIBDIR}
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+          LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+          ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
     )
   endif()
 
diff --git a/CMake/AbseilInstallDirs.cmake b/CMake/AbseilInstallDirs.cmake
deleted file mode 100644
index 6fc914b6..00000000
--- a/CMake/AbseilInstallDirs.cmake
+++ /dev/null
@@ -1,20 +0,0 @@
-include(GNUInstallDirs)
-
-# absl_VERSION is only set if we are an LTS release being installed, in which
-# case it may be into a system directory and so we need to make subdirectories
-# for each installed version of Abseil.  This mechanism is implemented in
-# Abseil's internal Copybara (https://github.com/google/copybara) workflows and
-# isn't visible in the CMake buildsystem itself.
-
-if(absl_VERSION)
-  set(ABSL_SUBDIR "${PROJECT_NAME}_${PROJECT_VERSION}")
-  set(ABSL_INSTALL_BINDIR "${CMAKE_INSTALL_BINDIR}/${ABSL_SUBDIR}")
-  set(ABSL_INSTALL_CONFIGDIR "${CMAKE_INSTALL_LIBDIR}/cmake/${ABSL_SUBDIR}")
-  set(ABSL_INSTALL_INCLUDEDIR "${CMAKE_INSTALL_INCLUDEDIR}/${ABSL_SUBDIR}")
-  set(ABSL_INSTALL_LIBDIR "${CMAKE_INSTALL_LIBDIR}/${ABSL_SUBDIR}")
-else()
-  set(ABSL_INSTALL_BINDIR "${CMAKE_INSTALL_BINDIR}")
-  set(ABSL_INSTALL_CONFIGDIR "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}")
-  set(ABSL_INSTALL_INCLUDEDIR "${CMAKE_INSTALL_INCLUDEDIR}")
-  set(ABSL_INSTALL_LIBDIR "${CMAKE_INSTALL_LIBDIR}")
-endif()
diff --git a/CMake/install_test_project/test.sh b/CMake/install_test_project/test.sh
index ddc7726b..a3d39773 100755
--- a/CMake/install_test_project/test.sh
+++ b/CMake/install_test_project/test.sh
@@ -13,70 +13,44 @@
 # 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.
-
-# "Unit" and integration tests for Absl CMake installation
-
-# TODO(absl-team): This script isn't fully hermetic because
-# -DABSL_USE_GOOGLETEST_HEAD=ON means that this script isn't pinned to a fixed
-# version of GoogleTest. This means that an upstream change to GoogleTest could
-# break this test. Fix this by allowing this script to pin to a known-good
-# version of GoogleTest.
+#
+# Unit and integration tests for Abseil LTS CMake installation
 
 # Fail on any error. Treat unset variables an error. Print commands as executed.
 set -euox pipefail
 
-install_absl() {
-  pushd "${absl_build_dir}"
-  if [[ "${#}" -eq 1 ]]; then
-    cmake -DCMAKE_INSTALL_PREFIX="${1}" "${absl_dir}"
-  else
-    cmake "${absl_dir}"
-  fi
-  cmake --build . --target install -- -j
-  popd
-}
-
-uninstall_absl() {
-  xargs rm < "${absl_build_dir}"/install_manifest.txt
-  rm -rf "${absl_build_dir}"
-  mkdir -p "${absl_build_dir}"
-}
-
-lts_install=""
-
-while getopts ":l" lts; do
-  case "${lts}" in
-    l )
-      lts_install="true"
-      ;;
-  esac
-done
+source ci/cmake_common.sh
 
 absl_dir=/abseil-cpp
-absl_build_dir=/buildfs/absl-build
+absl_build_dir=/buildfs
 project_dir="${absl_dir}"/CMake/install_test_project
 project_build_dir=/buildfs/project-build
 
-mkdir -p "${absl_build_dir}"
-mkdir -p "${project_build_dir}"
-
-if [[ "${lts_install}" ]]; then
-  install_dir="/usr/local"
-else
-  install_dir="${project_build_dir}"/install
+build_shared_libs="OFF"
+if [ "${LINK_TYPE:-}" = "DYNAMIC" ]; then
+  build_shared_libs="ON"
 fi
-mkdir -p "${install_dir}"
 
-# Test build, install, and link against installed abseil
-pushd "${project_build_dir}"
-if [[ "${lts_install}" ]]; then
-  install_absl
-  cmake "${project_dir}"
-else
-  install_absl "${install_dir}"
-  cmake "${project_dir}" -DCMAKE_PREFIX_PATH="${install_dir}"
-fi
+# Run the LTS transformations
+./create_lts.py 99998877
+
+# Install Abseil
+pushd "${absl_build_dir}"
+cmake "${absl_dir}" \
+  -DABSL_GOOGLETEST_DOWNLOAD_URL="${ABSL_GOOGLETEST_DOWNLOAD_URL}" \
+  -DCMAKE_BUILD_TYPE=Release \
+  -DBUILD_TESTING=ON \
+  -DBUILD_SHARED_LIBS="${build_shared_libs}"
+make -j $(nproc)
+ctest -j $(nproc)
+make install
+ldconfig
+popd
 
+# Test the project against the installed Abseil
+mkdir -p "${project_build_dir}"
+pushd "${project_build_dir}"
+cmake "${project_dir}"
 cmake --build . --target simple
 
 output="$(${project_build_dir}/simple "printme" 2>&1)"
@@ -88,32 +62,8 @@ fi
 
 popd
 
-# Test that we haven't accidentally made absl::abslblah
-pushd "${install_dir}"
-
-# Starting in CMake 3.12 the default install dir is lib$bit_width
-if [[ -d lib64 ]]; then
-  libdir="lib64"
-elif [[ -d lib ]]; then
-  libdir="lib"
-else
-  echo "ls *, */*, */*/*:"
-  ls *
-  ls */*
-  ls */*/*
-  echo "unknown lib dir"
-fi
-
-if [[ "${lts_install}" ]]; then
-  # LTS versions append the date of the release to the subdir.
-  # 9999/99/99 is the dummy date used in the local_lts workflow.
-  absl_subdir="absl_99999999"
-else
-  absl_subdir="absl"
-fi
-
-if ! grep absl::strings "${libdir}/cmake/${absl_subdir}/abslTargets.cmake"; then
-  cat "${libdir}"/cmake/absl/abslTargets.cmake
+if ! grep absl::strings "/usr/local/lib/cmake/absl/abslTargets.cmake"; then
+  cat "/usr/local/lib/cmake/absl/abslTargets.cmake"
   echo "CMake targets named incorrectly"
   exit 1
 fi
@@ -129,34 +79,18 @@ int main(int argc, char **argv) {
   return EXIT_SUCCESS;
 }
 EOF
-export PKG_CONFIG_PATH="${install_dir}/${libdir}/pkgconfig"
-pc_args=($(pkg-config --cflags --libs --static absl_str_format))
-g++ -static -o hello-abseil hello-abseil.cc "${pc_args[@]}"
+
+if [ "${LINK_TYPE:-}" != "DYNAMIC" ]; then
+  pc_args=($(pkg-config --cflags --libs --static absl_str_format))
+  g++ -static -o hello-abseil hello-abseil.cc "${pc_args[@]}"
+else
+  pc_args=($(pkg-config --cflags --libs absl_str_format))
+  g++ -o hello-abseil hello-abseil.cc "${pc_args[@]}"
+fi
 hello="$(./hello-abseil)"
 [[ "${hello}" == "Hello Abseil!" ]]
-popd
 
-uninstall_absl
 popd
 
-if [[ ! "${lts_install}" ]]; then
-  # Test that we warn if installed without a prefix or a system prefix
-  output="$(install_absl 2>&1)"
-  if [[ "${output}" != *"Please set CMAKE_INSTALL_PREFIX"* ]]; then
-    echo "Install without prefix didn't warn as expected. Output:"
-    echo "${output}"
-    exit 1
-  fi
-  uninstall_absl
-
-  output="$(install_absl /usr 2>&1)"
-  if [[ "${output}" != *"Please set CMAKE_INSTALL_PREFIX"* ]]; then
-    echo "Install with /usr didn't warn as expected. Output:"
-    echo "${output}"
-    exit 1
-  fi
-  uninstall_absl
-fi
-
 echo "Install test complete!"
 exit 0
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8843ee79..e09e335c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -45,7 +45,7 @@ endif (POLICY CMP0077)
 # This must come before the project() and include(CTest) lines.
 OPTION(BUILD_TESTING "Build tests" OFF)
 
-project(absl CXX)
+project(absl LANGUAGES CXX)
 include(CTest)
 
 # Output directory is correct by default for most build setups. However, when
@@ -67,8 +67,8 @@ list(APPEND CMAKE_MODULE_PATH
   ${CMAKE_CURRENT_LIST_DIR}/absl/copts
 )
 
-include(AbseilInstallDirs)
 include(CMakePackageConfigHelpers)
+include(GNUInstallDirs)
 include(AbseilDll)
 include(AbseilHelpers)
 
@@ -159,16 +159,16 @@ if(ABSL_ENABLE_INSTALL)
   # install as a subdirectory only
   install(EXPORT ${PROJECT_NAME}Targets
     NAMESPACE absl::
-    DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
   )
 
   configure_package_config_file(
     CMake/abslConfig.cmake.in
     "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
-    INSTALL_DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
+    INSTALL_DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
   )
   install(FILES "${PROJECT_BINARY_DIR}/${PROJECT_NAME}Config.cmake"
-    DESTINATION "${ABSL_INSTALL_CONFIGDIR}"
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
   )
 
   # Abseil only has a version in LTS releases.  This mechanism is accomplished
@@ -181,12 +181,12 @@ if(ABSL_ENABLE_INSTALL)
     )
 
     install(FILES "${PROJECT_BINARY_DIR}/${PROJECT_NAME}ConfigVersion.cmake"
-      DESTINATION ${ABSL_INSTALL_CONFIGDIR}
+      DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
     )
   endif()  # absl_VERSION
 
   install(DIRECTORY absl
-    DESTINATION ${ABSL_INSTALL_INCLUDEDIR}
+    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
     FILES_MATCHING
       PATTERN "*.inc"
       PATTERN "*.h"
diff --git a/absl/base/optimization.h b/absl/base/optimization.h
index 6332b625..d090be12 100644
--- a/absl/base/optimization.h
+++ b/absl/base/optimization.h
@@ -106,9 +106,10 @@
 // Cacheline aligning objects properly allows constructive memory sharing and
 // prevents destructive (or "false") memory sharing.
 //
-// NOTE: this macro should be replaced with usage of `alignas()` using
+// NOTE: callers should replace uses of this macro with `alignas()` using
 // `std::hardware_constructive_interference_size` and/or
-// `std::hardware_destructive_interference_size` when available within C++17.
+// `std::hardware_destructive_interference_size` when C++17 becomes available to
+// them.
 //
 // See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0154r1.html
 // for more information.
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h
index 00444a53..0bb38366 100644
--- a/absl/container/internal/btree.h
+++ b/absl/container/internal/btree.h
@@ -579,10 +579,10 @@ class btree_node {
   };
 
   // Leaves can have less than kNodeSlots values.
-  constexpr static layout_type LeafLayout(const int slots = kNodeSlots) {
+  constexpr static layout_type LeafLayout(const int slot_count = kNodeSlots) {
     return layout_type(/*parent*/ 1,
                        /*position, start, finish, max_count*/ 4,
-                       /*slots*/ slots,
+                       /*slots*/ slot_count,
                        /*children*/ 0);
   }
   constexpr static layout_type InternalLayout() {
@@ -591,8 +591,8 @@ class btree_node {
                        /*slots*/ kNodeSlots,
                        /*children*/ kNodeSlots + 1);
   }
-  constexpr static size_type LeafSize(const int slots = kNodeSlots) {
-    return LeafLayout(slots).AllocSize();
+  constexpr static size_type LeafSize(const int slot_count = kNodeSlots) {
+    return LeafLayout(slot_count).AllocSize();
   }
   constexpr static size_type InternalSize() {
     return InternalLayout().AllocSize();
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
index 80fc2cba..8615de8b 100644
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -792,7 +792,8 @@ class raw_hash_set {
   explicit raw_hash_set(size_t bucket_count, const hasher& hash = hasher(),
                         const key_equal& eq = key_equal(),
                         const allocator_type& alloc = allocator_type())
-      : ctrl_(EmptyGroup()), settings_(0, hash, eq, alloc) {
+      : ctrl_(EmptyGroup()),
+        settings_(0, HashtablezInfoHandle(), hash, eq, alloc) {
     if (bucket_count) {
       capacity_ = NormalizeCapacity(bucket_count);
       initialize_slots();
@@ -903,7 +904,7 @@ class raw_hash_set {
       auto target = find_first_non_full(ctrl_, hash, capacity_);
       set_ctrl(target.offset, H2(hash));
       emplace_at(target.offset, v);
-      infoz_.RecordInsert(hash, target.probe_length);
+      infoz().RecordInsert(hash, target.probe_length);
     }
     size_ = that.size();
     growth_left() -= that.size();
@@ -917,28 +918,27 @@ class raw_hash_set {
         slots_(absl::exchange(that.slots_, nullptr)),
         size_(absl::exchange(that.size_, 0)),
         capacity_(absl::exchange(that.capacity_, 0)),
-        infoz_(absl::exchange(that.infoz_, HashtablezInfoHandle())),
         // Hash, equality and allocator are copied instead of moved because
         // `that` must be left valid. If Hash is std::function<Key>, moving it
         // would create a nullptr functor that cannot be called.
-        settings_(that.settings_) {
-    // growth_left was copied above, reset the one from `that`.
-    that.growth_left() = 0;
-  }
+        settings_(absl::exchange(that.growth_left(), 0),
+                  absl::exchange(that.infoz(), HashtablezInfoHandle()),
+                  that.hash_ref(), that.eq_ref(), that.alloc_ref()) {}
 
   raw_hash_set(raw_hash_set&& that, const allocator_type& a)
       : ctrl_(EmptyGroup()),
         slots_(nullptr),
         size_(0),
         capacity_(0),
-        settings_(0, that.hash_ref(), that.eq_ref(), a) {
+        settings_(0, HashtablezInfoHandle(), that.hash_ref(), that.eq_ref(),
+                  a) {
     if (a == that.alloc_ref()) {
       std::swap(ctrl_, that.ctrl_);
       std::swap(slots_, that.slots_);
       std::swap(size_, that.size_);
       std::swap(capacity_, that.capacity_);
       std::swap(growth_left(), that.growth_left());
-      std::swap(infoz_, that.infoz_);
+      std::swap(infoz(), that.infoz());
     } else {
       reserve(that.size());
       // Note: this will copy elements of dense_set and unordered_set instead of
@@ -1009,7 +1009,7 @@ class raw_hash_set {
       reset_growth_left();
     }
     assert(empty());
-    infoz_.RecordStorageChanged(0, capacity_);
+    infoz().RecordStorageChanged(0, capacity_);
   }
 
   // This overload kicks in when the argument is an rvalue of insertable and
@@ -1301,7 +1301,7 @@ class raw_hash_set {
     swap(growth_left(), that.growth_left());
     swap(hash_ref(), that.hash_ref());
     swap(eq_ref(), that.eq_ref());
-    swap(infoz_, that.infoz_);
+    swap(infoz(), that.infoz());
     SwapAlloc(alloc_ref(), that.alloc_ref(),
               typename AllocTraits::propagate_on_container_swap{});
   }
@@ -1310,7 +1310,7 @@ class raw_hash_set {
     if (n == 0 && capacity_ == 0) return;
     if (n == 0 && size_ == 0) {
       destroy_slots();
-      infoz_.RecordStorageChanged(0, 0);
+      infoz().RecordStorageChanged(0, 0);
       return;
     }
     // bitor is a faster way of doing `max` here. We will round up to the next
@@ -1528,7 +1528,7 @@ class raw_hash_set {
 
     set_ctrl(index, was_never_full ? kEmpty : kDeleted);
     growth_left() += was_never_full;
-    infoz_.RecordErase();
+    infoz().RecordErase();
   }
 
   void initialize_slots() {
@@ -1545,7 +1545,7 @@ class raw_hash_set {
     // bound more carefully.
     if (std::is_same<SlotAlloc, std::allocator<slot_type>>::value &&
         slots_ == nullptr) {
-      infoz_ = Sample();
+      infoz() = Sample();
     }
 
     auto layout = MakeLayout(capacity_);
@@ -1555,7 +1555,7 @@ class raw_hash_set {
     slots_ = layout.template Pointer<1>(mem);
     reset_ctrl();
     reset_growth_left();
-    infoz_.RecordStorageChanged(size_, capacity_);
+    infoz().RecordStorageChanged(size_, capacity_);
   }
 
   void destroy_slots() {
@@ -1603,7 +1603,7 @@ class raw_hash_set {
       Deallocate<Layout::Alignment()>(&alloc_ref(), old_ctrl,
                                       layout.AllocSize());
     }
-    infoz_.RecordRehash(total_probe_length);
+    infoz().RecordRehash(total_probe_length);
   }
 
   void drop_deletes_without_resize() ABSL_ATTRIBUTE_NOINLINE {
@@ -1669,7 +1669,7 @@ class raw_hash_set {
       }
     }
     reset_growth_left();
-    infoz_.RecordRehash(total_probe_length);
+    infoz().RecordRehash(total_probe_length);
   }
 
   void rehash_and_grow_if_necessary() {
@@ -1743,7 +1743,7 @@ class raw_hash_set {
     ++size_;
     growth_left() -= IsEmpty(ctrl_[target.offset]);
     set_ctrl(target.offset, H2(hash));
-    infoz_.RecordInsert(hash, target.probe_length);
+    infoz().RecordInsert(hash, target.probe_length);
     return target.offset;
   }
 
@@ -1800,13 +1800,15 @@ class raw_hash_set {
 
   size_t& growth_left() { return settings_.template get<0>(); }
 
-  hasher& hash_ref() { return settings_.template get<1>(); }
-  const hasher& hash_ref() const { return settings_.template get<1>(); }
-  key_equal& eq_ref() { return settings_.template get<2>(); }
-  const key_equal& eq_ref() const { return settings_.template get<2>(); }
-  allocator_type& alloc_ref() { return settings_.template get<3>(); }
+  HashtablezInfoHandle& infoz() { return settings_.template get<1>(); }
+
+  hasher& hash_ref() { return settings_.template get<2>(); }
+  const hasher& hash_ref() const { return settings_.template get<2>(); }
+  key_equal& eq_ref() { return settings_.template get<3>(); }
+  const key_equal& eq_ref() const { return settings_.template get<3>(); }
+  allocator_type& alloc_ref() { return settings_.template get<4>(); }
   const allocator_type& alloc_ref() const {
-    return settings_.template get<3>();
+    return settings_.template get<4>();
   }
 
   // TODO(alkis): Investigate removing some of these fields:
@@ -1816,10 +1818,11 @@ class raw_hash_set {
   slot_type* slots_ = nullptr;     // [capacity * slot_type]
   size_t size_ = 0;                // number of full slots
   size_t capacity_ = 0;            // total number of slots
-  HashtablezInfoHandle infoz_;
-  absl::container_internal::CompressedTuple<size_t /* growth_left */, hasher,
+  absl::container_internal::CompressedTuple<size_t /* growth_left */,
+                                            HashtablezInfoHandle, hasher,
                                             key_equal, allocator_type>
-      settings_{0, hasher{}, key_equal{}, allocator_type{}};
+      settings_{0, HashtablezInfoHandle{}, hasher{}, key_equal{},
+                allocator_type{}};
 };
 
 // Erases all elements that satisfy the predicate `pred` from the container `c`.
diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc
index 81c4b47c..7dac65a0 100644
--- a/absl/container/internal/raw_hash_set_test.cc
+++ b/absl/container/internal/raw_hash_set_test.cc
@@ -419,6 +419,13 @@ TEST(Table, EmptyFunctorOptimization) {
     size_t growth_left;
     void* infoz;
   };
+  struct MockTableInfozDisabled {
+    void* ctrl;
+    void* slots;
+    size_t size;
+    size_t capacity;
+    size_t growth_left;
+  };
   struct StatelessHash {
     size_t operator()(absl::string_view) const { return 0; }
   };
@@ -426,17 +433,27 @@ TEST(Table, EmptyFunctorOptimization) {
     size_t dummy;
   };
 
-  EXPECT_EQ(
-      sizeof(MockTable),
-      sizeof(
-          raw_hash_set<StringPolicy, StatelessHash,
-                       std::equal_to<absl::string_view>, std::allocator<int>>));
-
-  EXPECT_EQ(
-      sizeof(MockTable) + sizeof(StatefulHash),
-      sizeof(
-          raw_hash_set<StringPolicy, StatefulHash,
-                       std::equal_to<absl::string_view>, std::allocator<int>>));
+  if (std::is_empty<HashtablezInfoHandle>::value) {
+    EXPECT_EQ(sizeof(MockTableInfozDisabled),
+              sizeof(raw_hash_set<StringPolicy, StatelessHash,
+                                  std::equal_to<absl::string_view>,
+                                  std::allocator<int>>));
+
+    EXPECT_EQ(sizeof(MockTableInfozDisabled) + sizeof(StatefulHash),
+              sizeof(raw_hash_set<StringPolicy, StatefulHash,
+                                  std::equal_to<absl::string_view>,
+                                  std::allocator<int>>));
+  } else {
+    EXPECT_EQ(sizeof(MockTable),
+              sizeof(raw_hash_set<StringPolicy, StatelessHash,
+                                  std::equal_to<absl::string_view>,
+                                  std::allocator<int>>));
+
+    EXPECT_EQ(sizeof(MockTable) + sizeof(StatefulHash),
+              sizeof(raw_hash_set<StringPolicy, StatefulHash,
+                                  std::equal_to<absl::string_view>,
+                                  std::allocator<int>>));
+  }
 }
 
 TEST(Table, Empty) {
diff --git a/absl/debugging/internal/demangle.cc b/absl/debugging/internal/demangle.cc
index 46cdb67b..5cd56320 100644
--- a/absl/debugging/internal/demangle.cc
+++ b/absl/debugging/internal/demangle.cc
@@ -386,24 +386,28 @@ static bool IsDigit(char c) { return c >= '0' && c <= '9'; }
 // by GCC 4.5.x and later versions (and our locally-modified version of GCC
 // 4.4.x) to indicate functions which have been cloned during optimization.
 // We treat any sequence (.<alpha>+.<digit>+)+ as a function clone suffix.
+// Additionally, '_' is allowed along with the alphanumeric sequence.
 static bool IsFunctionCloneSuffix(const char *str) {
   size_t i = 0;
   while (str[i] != '\0') {
-    // Consume a single .<alpha>+.<digit>+ sequence.
-    if (str[i] != '.' || !IsAlpha(str[i + 1])) {
-      return false;
+    bool parsed = false;
+    // Consume a single [.<alpha> | _]*[.<digit>]* sequence.
+    if (str[i] == '.' && (IsAlpha(str[i + 1]) || str[i + 1] == '_')) {
+      parsed = true;
+      i += 2;
+      while (IsAlpha(str[i]) || str[i] == '_') {
+        ++i;
+      }
     }
-    i += 2;
-    while (IsAlpha(str[i])) {
-      ++i;
+    if (str[i] == '.' && IsDigit(str[i + 1])) {
+      parsed = true;
+      i += 2;
+      while (IsDigit(str[i])) {
+        ++i;
+      }
     }
-    if (str[i] != '.' || !IsDigit(str[i + 1])) {
+    if (!parsed)
       return false;
-    }
-    i += 2;
-    while (IsDigit(str[i])) {
-      ++i;
-    }
   }
   return true;  // Consumed everything in "str".
 }
diff --git a/absl/debugging/internal/demangle_test.cc b/absl/debugging/internal/demangle_test.cc
index 0bed7359..6b142902 100644
--- a/absl/debugging/internal/demangle_test.cc
+++ b/absl/debugging/internal/demangle_test.cc
@@ -70,12 +70,34 @@ TEST(Demangle, Clones) {
   EXPECT_STREQ("Foo()", tmp);
   EXPECT_TRUE(Demangle("_ZL3Foov.isra.2.constprop.18", tmp, sizeof(tmp)));
   EXPECT_STREQ("Foo()", tmp);
-  // Invalid (truncated), should not demangle.
-  EXPECT_FALSE(Demangle("_ZL3Foov.clo", tmp, sizeof(tmp)));
+  // Demangle suffixes produced by -funique-internal-linkage-names.
+  EXPECT_TRUE(Demangle("_ZL3Foov.__uniq.12345", tmp, sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  EXPECT_TRUE(Demangle("_ZL3Foov.__uniq.12345.isra.2.constprop.18", tmp,
+                       sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // Suffixes without the number should also demangle.
+  EXPECT_TRUE(Demangle("_ZL3Foov.clo", tmp, sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // Suffixes with just the number should also demangle.
+  EXPECT_TRUE(Demangle("_ZL3Foov.123", tmp, sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // (.clone. followed by non-number), should also demangle.
+  EXPECT_TRUE(Demangle("_ZL3Foov.clone.foo", tmp, sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // (.clone. followed by multiple numbers), should also demangle.
+  EXPECT_TRUE(Demangle("_ZL3Foov.clone.123.456", tmp, sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // (a long valid suffix), should demangle.
+  EXPECT_TRUE(Demangle("_ZL3Foov.part.9.165493.constprop.775.31805", tmp,
+                       sizeof(tmp)));
+  EXPECT_STREQ("Foo()", tmp);
+  // Invalid (. without anything else), should not demangle.
+  EXPECT_FALSE(Demangle("_ZL3Foov.", tmp, sizeof(tmp)));
+  // Invalid (. with mix of alpha and digits), should not demangle.
+  EXPECT_FALSE(Demangle("_ZL3Foov.abc123", tmp, sizeof(tmp)));
   // Invalid (.clone. not followed by number), should not demangle.
   EXPECT_FALSE(Demangle("_ZL3Foov.clone.", tmp, sizeof(tmp)));
-  // Invalid (.clone. followed by non-number), should not demangle.
-  EXPECT_FALSE(Demangle("_ZL3Foov.clone.foo", tmp, sizeof(tmp)));
   // Invalid (.constprop. not followed by number), should not demangle.
   EXPECT_FALSE(Demangle("_ZL3Foov.isra.2.constprop.", tmp, sizeof(tmp)));
 }
diff --git a/absl/debugging/leak_check.cc b/absl/debugging/leak_check.cc
index ff904955..db9d5d09 100644
--- a/absl/debugging/leak_check.cc
+++ b/absl/debugging/leak_check.cc
@@ -38,6 +38,7 @@ ABSL_NAMESPACE_END
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 bool HaveLeakSanitizer() { return true; }
+bool FindAndReportLeaks() { return __lsan_do_recoverable_leak_check(); }
 void DoIgnoreLeak(const void* ptr) { __lsan_ignore_object(ptr); }
 void RegisterLivePointers(const void* ptr, size_t size) {
   __lsan_register_root_region(ptr, size);
diff --git a/absl/debugging/leak_check.h b/absl/debugging/leak_check.h
index b66a81c3..61c3216f 100644
--- a/absl/debugging/leak_check.h
+++ b/absl/debugging/leak_check.h
@@ -71,6 +71,19 @@ T* IgnoreLeak(T* ptr) {
   return ptr;
 }
 
+// FindAndReportLeaks()
+//
+// If any leaks are detected, prints a leak report and returns true.  This
+// function may be called repeatedly, and does not affect end-of-process leak
+// checking.
+//
+// Example:
+// if (FindAndReportLeaks()) {
+//   ... diagnostic already printed. Exit with failure code.
+//   exit(1)
+// }
+bool FindAndReportLeaks();
+
 // LeakCheckDisabler
 //
 // This helper class indicates that any heap allocations done in the code block
diff --git a/absl/status/internal/status_internal.h b/absl/status/internal/status_internal.h
index 279f8f55..99a2d964 100644
--- a/absl/status/internal/status_internal.h
+++ b/absl/status/internal/status_internal.h
@@ -19,6 +19,17 @@
 #include "absl/container/inlined_vector.h"
 #include "absl/strings/cord.h"
 
+#ifndef SWIG
+// Disabled for SWIG as it doesn't parse attributes correctly.
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+// Returned Status objects may not be ignored. Codesearch doesn't handle ifdefs
+// as part of a class definitions (b/6995610), so we use a forward declaration.
+class ABSL_MUST_USE_RESULT Status;
+ABSL_NAMESPACE_END
+}  // namespace absl
+#endif  // !SWIG
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
diff --git a/absl/status/status.h b/absl/status/status.h
index df9e330c..61486fee 100644
--- a/absl/status/status.h
+++ b/absl/status/status.h
@@ -291,6 +291,8 @@ enum class StatusToStringMode : int {
   kWithNoExtraData = 0,
   // ToString will contain the payloads.
   kWithPayload = 1 << 0,
+  // ToString will include all the extra data this Status has.
+  kWithEverything = ~kWithNoExtraData,
 };
 
 // absl::StatusToStringMode is specified as a bitmask type, which means the
@@ -410,7 +412,12 @@ inline StatusToStringMode& operator^=(StatusToStringMode& lhs,
 //     return result;
 //   }
 //
-class ABSL_MUST_USE_RESULT Status final {
+// For documentation see https://abseil.io/docs/cpp/guides/status.
+//
+// Returned Status objects may not be ignored. status_internal.h has a forward
+// declaration of the form
+// class ABSL_MUST_USE_RESULT Status;
+class Status final {
  public:
   // Constructors
 
diff --git a/absl/status/status_test.cc b/absl/status/status_test.cc
index 7116ba67..0e1a43ce 100644
--- a/absl/status/status_test.cc
+++ b/absl/status/status_test.cc
@@ -292,6 +292,10 @@ TEST(Status, ToStringMode) {
               AllOf(HasSubstr("INTERNAL: fail"), HasSubstr("[foo='bar']"),
                     HasSubstr("[bar='\\xff']")));
 
+  EXPECT_THAT(s.ToString(absl::StatusToStringMode::kWithEverything),
+              AllOf(HasSubstr("INTERNAL: fail"), HasSubstr("[foo='bar']"),
+                    HasSubstr("[bar='\\xff']")));
+
   EXPECT_THAT(s.ToString(~absl::StatusToStringMode::kWithPayload),
               AllOf(HasSubstr("INTERNAL: fail"), Not(HasSubstr("[foo='bar']")),
                     Not(HasSubstr("[bar='\\xff']"))));
diff --git a/absl/status/statusor.h b/absl/status/statusor.h
index 469d486f..b7c55cc8 100644
--- a/absl/status/statusor.h
+++ b/absl/status/statusor.h
@@ -135,7 +135,7 @@ class ABSL_MUST_USE_RESULT StatusOr;
 //
 // NOTE: using `absl::StatusOr<T>::value()` when no valid value is present will
 // throw an exception if exceptions are enabled or terminate the process when
-// execeptions are not enabled.
+// exceptions are not enabled.
 //
 // Example:
 //
diff --git a/absl/strings/numbers.h b/absl/strings/numbers.h
index ffc738fa..1780bb44 100644
--- a/absl/strings/numbers.h
+++ b/absl/strings/numbers.h
@@ -124,6 +124,7 @@ inline void PutTwoDigits(size_t i, char* buf) {
 }
 
 // safe_strto?() functions for implementing SimpleAtoi()
+
 bool safe_strto32_base(absl::string_view text, int32_t* value, int base);
 bool safe_strto64_base(absl::string_view text, int64_t* value, int base);
 bool safe_strto128_base(absl::string_view text, absl::int128* value,
diff --git a/ci/cmake_install_test.sh b/ci/cmake_install_test.sh
index 5bf540c5..ffc6b516 100755
--- a/ci/cmake_install_test.sh
+++ b/ci/cmake_install_test.sh
@@ -20,18 +20,24 @@ if [[ -z ${ABSEIL_ROOT:-} ]]; then
   ABSEIL_ROOT="$(realpath $(dirname ${0})/..)"
 fi
 
+if [[ -z ${LINK_TYPE:-} ]]; then
+  LINK_TYPE="STATIC DYNAMIC"
+fi
+
 source "${ABSEIL_ROOT}/ci/cmake_common.sh"
 
 source "${ABSEIL_ROOT}/ci/linux_docker_containers.sh"
 readonly DOCKER_CONTAINER=${LINUX_GCC_LATEST_CONTAINER}
 
-time docker run \
-    --mount type=bind,source="${ABSEIL_ROOT}",target=/abseil-cpp,readonly \
-    --workdir=/abseil-cpp \
+for link_type in ${LINK_TYPE}; do
+  time docker run \
+    --mount type=bind,source="${ABSEIL_ROOT}",target=/abseil-cpp-ro,readonly \
     --tmpfs=/buildfs:exec \
+    --tmpfs=/abseil-cpp:exec \
+    --workdir=/abseil-cpp \
     --cap-add=SYS_PTRACE \
+    -e "LINK_TYPE=${link_type}" \
     --rm \
-    -e CFLAGS="-Werror" \
-    -e CXXFLAGS="-Werror" \
     ${DOCKER_CONTAINER} \
-    /bin/bash CMake/install_test_project/test.sh $@
+    /bin/bash -c "cp -r /abseil-cpp-ro/* . && CMake/install_test_project/test.sh"
+done
diff --git a/create_lts.py b/create_lts.py
new file mode 100755
index 00000000..a98c76b4
--- /dev/null
+++ b/create_lts.py
@@ -0,0 +1,121 @@
+#!/usr/bin/env python
+#
+# Copyright 2021 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.
+"""A script to do source transformations to create a new LTS release.
+
+   Usage: ./create_lts.py YYYYMMDD
+"""
+
+import sys
+
+
+def ReplaceStringsInFile(filename, replacement_dict):
+  """Performs textual replacements in a file.
+
+  Rewrites filename with the keys in replacement_dict replaced with
+  their values. This function assumes the file can fit in memory.
+
+  Args:
+    filename: the filename to perform the replacement on
+    replacement_dict: a dictionary of key strings to be replaced with their
+      values
+
+  Raises:
+    Exception: A failure occured
+  """
+  f = open(filename, 'r')
+  content = f.read()
+  f.close()
+
+  for key, value in replacement_dict.items():
+    original = content
+    content = content.replace(key, value)
+    if content == original:
+      raise Exception('Failed to find {} in {}'.format(key, filename))
+
+  f = open(filename, 'w')
+  f.write(content)
+  f.close()
+
+
+def StripContentBetweenTags(filename, strip_begin_tag, strip_end_tag):
+  """Strip contents from a file.
+
+  Rewrites filename with by removing all content between
+  strip_begin_tag and strip_end_tag, including the tags themselves.
+
+  Args:
+    filename: the filename to perform the replacement on
+    strip_begin_tag: the start of the content to be removed
+    strip_end_tag: the end of the content to be removed
+
+  Raises:
+    Exception: A failure occured
+  """
+  f = open(filename, 'r')
+  content = f.read()
+  f.close()
+
+  while True:
+    begin = content.find(strip_begin_tag)
+    if begin == -1:
+      break
+    end = content.find(strip_end_tag, begin + len(strip_begin_tag))
+    if end == -1:
+      raise Exception('{}: imbalanced strip begin ({}) and '
+                      'end ({}) tags'.format(filename, strip_begin_tag,
+                                             strip_end_tag))
+    content = content.replace(content[begin:end + len(strip_end_tag)], '')
+
+  f = open(filename, 'w')
+  f.write(content)
+  f.close()
+
+
+def main(argv):
+  if len(argv) != 2:
+    print('Usage: {} YYYYMMDD'.format(sys.argv[0], file=sys.stderr))
+    sys.exit(1)
+
+  datestamp = sys.argv[1]
+  if len(datestamp) != 8 or not datestamp.isdigit():
+    raise Exception(
+        'datestamp={} is not in the YYYYMMDD format'.format(datestamp))
+
+  # Replacement directives go here.
+  ReplaceStringsInFile(
+      'absl/base/options.h', {
+          '#define ABSL_OPTION_USE_INLINE_NAMESPACE 0':
+              '#define ABSL_OPTION_USE_INLINE_NAMESPACE 1',
+          '#define ABSL_OPTION_INLINE_NAMESPACE_NAME head':
+              '#define ABSL_OPTION_INLINE_NAMESPACE_NAME lts_{}'.format(
+                  datestamp)
+      })
+  ReplaceStringsInFile(
+      'CMakeLists.txt', {
+          'project(absl LANGUAGES CXX)':
+              'project(absl LANGUAGES CXX VERSION {})'.format(datestamp)
+      })
+  # Set the SOVERSION to YYYYMMDD.0.0 - The first 0 means we only have
+  # ABI compatible changes, and the second 0 means we can increment it
+  # to mark changes as ABI-compatible, for patch releases.
+  ReplaceStringsInFile('CMake/AbseilHelpers.cmake',
+                       {'SOVERSION 0': 'SOVERSION "{}.0.0"'.format(datestamp)})
+  StripContentBetweenTags('CMakeLists.txt', '# absl:lts-remove-begin',
+                          '# absl:lts-remove-end')
+
+
+if __name__ == '__main__':
+  main(sys.argv)
-- 
cgit v1.2.3


From 1fdbe1ea1b8c835c11ed6fbec4d4259ad104f765 Mon Sep 17 00:00:00 2001
From: Abseil Team <absl-team@google.com>
Date: Tue, 23 Mar 2021 15:07:11 -0700
Subject: Export of internal Abseil changes

--
4b566a7deeba5db473c83f4924c1d182a002779f by Abseil Team <absl-team@google.com>:

Add absl::LeakCheckerIsActive to check whether a leak checker is built into the
target and enabled. For LeakSanitizer, it is by default enabled unless
__lsan_is_turned_off() is defined and returns true.

PiperOrigin-RevId: 364654465

--
0a56ff5310b66f9d1ff5e5e2a053335ecfb5c75b by Abseil Team <absl-team@google.com>:

Update absl::FromTM documentation to reflect implementation.

PiperOrigin-RevId: 364388743
GitOrigin-RevId: 4b566a7deeba5db473c83f4924c1d182a002779f
Change-Id: I8df35b761b532e79d620f484153083c3499ef55b
---
 absl/debugging/BUILD.bazel        |  2 ++
 absl/debugging/leak_check.cc      | 15 +++++++++++++++
 absl/debugging/leak_check.h       |  6 ++++++
 absl/debugging/leak_check_test.cc |  2 ++
 absl/time/time.h                  | 14 +++++++++-----
 5 files changed, 34 insertions(+), 5 deletions(-)

(limited to 'absl/debugging/leak_check.h')

diff --git a/absl/debugging/BUILD.bazel b/absl/debugging/BUILD.bazel
index e7fd1152..5385bcb6 100644
--- a/absl/debugging/BUILD.bazel
+++ b/absl/debugging/BUILD.bazel
@@ -260,6 +260,7 @@ cc_library(
     visibility = ["//visibility:private"],
     deps = [
         "//absl/base:config",
+        "//absl/base:core_headers",
     ],
 )
 
@@ -273,6 +274,7 @@ cc_library(
     visibility = ["//visibility:private"],
     deps = [
         "//absl/base:config",
+        "//absl/base:core_headers",
     ],
 )
 
diff --git a/absl/debugging/leak_check.cc b/absl/debugging/leak_check.cc
index db9d5d09..764ca0ad 100644
--- a/absl/debugging/leak_check.cc
+++ b/absl/debugging/leak_check.cc
@@ -16,6 +16,7 @@
 // When lsan is not linked in, these functions are not available,
 // therefore Abseil code which depends on these functions is conditioned on the
 // definition of LEAK_SANITIZER.
+#include "absl/base/attributes.h"
 #include "absl/debugging/leak_check.h"
 
 #ifndef LEAK_SANITIZER
@@ -23,6 +24,7 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 bool HaveLeakSanitizer() { return false; }
+bool LeakCheckerIsActive() { return false; }
 void DoIgnoreLeak(const void*) { }
 void RegisterLivePointers(const void*, size_t) { }
 void UnRegisterLivePointers(const void*, size_t) { }
@@ -35,9 +37,22 @@ ABSL_NAMESPACE_END
 
 #include <sanitizer/lsan_interface.h>
 
+#if ABSL_HAVE_ATTRIBUTE_WEAK
+extern "C" ABSL_ATTRIBUTE_WEAK int __lsan_is_turned_off();
+#endif
+
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 bool HaveLeakSanitizer() { return true; }
+
+#if ABSL_HAVE_ATTRIBUTE_WEAK
+bool LeakCheckerIsActive() {
+  return !(&__lsan_is_turned_off && __lsan_is_turned_off());
+}
+#else
+bool LeakCheckerIsActive() { return true; }
+#endif
+
 bool FindAndReportLeaks() { return __lsan_do_recoverable_leak_check(); }
 void DoIgnoreLeak(const void* ptr) { __lsan_ignore_object(ptr); }
 void RegisterLivePointers(const void* ptr, size_t size) {
diff --git a/absl/debugging/leak_check.h b/absl/debugging/leak_check.h
index 61c3216f..5fc2b052 100644
--- a/absl/debugging/leak_check.h
+++ b/absl/debugging/leak_check.h
@@ -43,6 +43,12 @@ ABSL_NAMESPACE_BEGIN
 // currently built into this target.
 bool HaveLeakSanitizer();
 
+// LeakCheckerIsActive()
+//
+// Returns true if a leak-checking sanitizer (either ASan or standalone LSan) is
+// currently built into this target and is turned on.
+bool LeakCheckerIsActive();
+
 // DoIgnoreLeak()
 //
 // Implements `IgnoreLeak()` below. This function should usually
diff --git a/absl/debugging/leak_check_test.cc b/absl/debugging/leak_check_test.cc
index b5cc4874..9fcfc8e5 100644
--- a/absl/debugging/leak_check_test.cc
+++ b/absl/debugging/leak_check_test.cc
@@ -23,8 +23,10 @@ namespace {
 TEST(LeakCheckTest, DetectLeakSanitizer) {
 #ifdef ABSL_EXPECT_LEAK_SANITIZER
   EXPECT_TRUE(absl::HaveLeakSanitizer());
+  EXPECT_TRUE(absl::LeakCheckerIsActive());
 #else
   EXPECT_FALSE(absl::HaveLeakSanitizer());
+  EXPECT_FALSE(absl::LeakCheckerIsActive());
 #endif
 }
 
diff --git a/absl/time/time.h b/absl/time/time.h
index d9ad1aed..2df68581 100644
--- a/absl/time/time.h
+++ b/absl/time/time.h
@@ -1180,11 +1180,15 @@ inline Time FromDateTime(int64_t year, int mon, int day, int hour,
 //
 // Converts the `tm_year`, `tm_mon`, `tm_mday`, `tm_hour`, `tm_min`, and
 // `tm_sec` fields to an `absl::Time` using the given time zone. See ctime(3)
-// for a description of the expected values of the tm fields. If the indicated
-// time instant is not unique (see `absl::TimeZone::At(absl::CivilSecond)`
-// above), the `tm_isdst` field is consulted to select the desired instant
-// (`tm_isdst` > 0 means DST, `tm_isdst` == 0 means no DST, `tm_isdst` < 0
-// means use the post-transition offset).
+// for a description of the expected values of the tm fields. If the civil time
+// is unique (see `absl::TimeZone::At(absl::CivilSecond)` above), the matching
+// time instant is returned.  Otherwise, the `tm_isdst` field is consulted to
+// choose between the possible results.  For a repeated civil time, `tm_isdst !=
+// 0` returns the matching DST instant, while `tm_isdst == 0` returns the
+// matching non-DST instant.  For a skipped civil time there is no matching
+// instant, so `tm_isdst != 0` returns the DST instant, and `tm_isdst == 0`
+// returns the non-DST instant, that would have matched if the transition never
+// happened.
 Time FromTM(const struct tm& tm, TimeZone tz);
 
 // ToTM()
-- 
cgit v1.2.3