Export of internal Abseil changes

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730bb88bee556aa11fa19aa33e1434cb6fa78985 by Evan Brown <ezb@google.com>:

Support missing allocator-related constructors in b-tree. See [reference](https://en.cppreference.com/w/cpp/container/set/set).

Also use allocator_traits::select_on_container_copy_construction() to get allocator for copy construction.

PiperOrigin-RevId: 339058322

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b6cc121689ae3e452d1db2d66122cb198d25142b by Derek Mauro <dmauro@google.com>:

Fix more sign-compare warnings

PiperOrigin-RevId: 339057920

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0e2c62da1dcaf6529abab952bdcc96c6de2d9506 by Abseil Team <absl-team@google.com>:

Add missing <limits> include

PiperOrigin-RevId: 339054753

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d5a9ec2d1e40fe6359e720942e4955009ee415ec by Derek Mauro <dmauro@google.com>:

Stop disabling sign-compare warnings for non-test targets.
Our users complain about these.

This does not catch issues in header-only libraries (like btree.h)
but we may work on those in the future

PiperOrigin-RevId: 338967089

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0c062c542a4c61ea0f65d25811827c0858e3adde by Abseil Team <absl-team@google.com>:

Improve cache-locality for ThreadIdentity and PerThreadSynch.

This is a change based on an observation in RPC benchmarks that shows
significant cycles being spent in waking up a thread, 99.8% of which
was on cache misses. Investigating this a bit more, it turns out to
be due to sharing the cache line with the waiter state.

To fix this issue, the following changes are introduced:
- Reorder fields in PerThreadSync so that it fits in a single cache line
  The size of this structure was 80 bytes before this change.
  Note: Manually inspected all booleans to make sure they are not modified by
        multiple threads concurrently.

PiperOrigin-RevId: 338852058

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a90d6f2b2346385017e32dd8ae1b5ca691a5863f by Derek Mauro <dmauro@google.com>:

Delete GCC 4.9 test script. It is no longer supported

PiperOrigin-RevId: 338779452

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7274008d4757e88869110be9db39d03d911ae2b5 by Abseil Team <absl-team@google.com>:

Fix the usage example in which SetFlag should take a pointer.

PiperOrigin-RevId: 338744529
GitOrigin-RevId: 730bb88bee556aa11fa19aa33e1434cb6fa78985
Change-Id: Iff99594c4022e60e482a392d334b376c7ae8883e

2 files changed, 0 insertions, 90 deletions

diff --git a/ci/linux_docker_containers.sh b/ci/linux_docker_containers.sh
index b96fe890..afad301e 100644
--- a/ci/linux_docker_containers.sh
+++ b/ci/linux_docker_containers.sh
@@ -19,4 +19,3 @@ readonly LINUX_ALPINE_CONTAINER="gcr.io/google.com/absl-177019/alpine:20191016"
 readonly LINUX_CLANG_LATEST_CONTAINER="gcr.io/google.com/absl-177019/linux_hybrid-latest:20201008"
 readonly LINUX_GCC_LATEST_CONTAINER="gcr.io/google.com/absl-177019/linux_hybrid-latest:20201008"
 readonly LINUX_GCC_FLOOR_CONTAINER="gcr.io/google.com/absl-177019/linux_gcc-floor:20201015"
-readonly LINUX_GCC_49_CONTAINER="gcr.io/google.com/absl-177019/linux_gcc-4.9:20191018"
diff --git a/ci/linux_gcc-4.9_libstdcxx_bazel.sh b/ci/linux_gcc-4.9_libstdcxx_bazel.sh
deleted file mode 100755
index 16f927bd..00000000
--- a/ci/linux_gcc-4.9_libstdcxx_bazel.sh
+++ /dev/null
@@ -1,89 +0,0 @@
-#!/bin/bash
-#
-# Copyright 2019 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.
-
-# This script that can be invoked to test abseil-cpp in a hermetic environment
-# using a Docker image on Linux. You must have Docker installed to use this
-# script.
-
-set -euox pipefail
-
-if [[ -z ${ABSEIL_ROOT:-} ]]; then
-  ABSEIL_ROOT="$(realpath $(dirname ${0})/..)"
-fi
-
-if [[ -z ${STD:-} ]]; then
-  STD="c++11 c++14"
-fi
-
-if [[ -z ${COMPILATION_MODE:-} ]]; then
-  COMPILATION_MODE="fastbuild opt"
-fi
-
-if [[ -z ${EXCEPTIONS_MODE:-} ]]; then
-  EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
-fi
-
-source "${ABSEIL_ROOT}/ci/linux_docker_containers.sh"
-readonly DOCKER_CONTAINER=${LINUX_GCC_49_CONTAINER}
-
-# USE_BAZEL_CACHE=1 only works on Kokoro.
-# Without access to the credentials this won't work.
-if [[ ${USE_BAZEL_CACHE:-0} -ne 0 ]]; then
-  DOCKER_EXTRA_ARGS="--mount type=bind,source=${KOKORO_KEYSTORE_DIR},target=/keystore,readonly ${DOCKER_EXTRA_ARGS:-}"
-  # Bazel doesn't track changes to tools outside of the workspace
-  # (e.g. /usr/bin/gcc), so by appending the docker container to the
-  # remote_http_cache url, we make changes to the container part of
-  # the cache key. Hashing the key is to make it shorter and url-safe.
-  container_key=$(echo ${DOCKER_CONTAINER} | sha256sum | head -c 16)
-  BAZEL_EXTRA_ARGS="--remote_http_cache=https://storage.googleapis.com/absl-bazel-remote-cache/${container_key} --google_credentials=/keystore/73103_absl-bazel-remote-cache ${BAZEL_EXTRA_ARGS:-}"
-fi
-
-# Avoid depending on external sites like GitHub by checking --distdir for
-# external dependencies first.
-# https://docs.bazel.build/versions/master/guide.html#distdir
-if [[ ${KOKORO_GFILE_DIR:-} ]] && [[ -d "${KOKORO_GFILE_DIR}/distdir" ]]; then
-  DOCKER_EXTRA_ARGS="--mount type=bind,source=${KOKORO_GFILE_DIR}/distdir,target=/distdir,readonly ${DOCKER_EXTRA_ARGS:-}"
-  BAZEL_EXTRA_ARGS="--distdir=/distdir ${BAZEL_EXTRA_ARGS:-}"
-fi
-
-for std in ${STD}; do
-  for compilation_mode in ${COMPILATION_MODE}; do
-    for exceptions_mode in ${EXCEPTIONS_MODE}; do
-      echo "--------------------------------------------------------------------"
-      time docker run \
-        --mount type=bind,source="${ABSEIL_ROOT}",target=/abseil-cpp,readonly \
-        --workdir=/abseil-cpp \
-        --cap-add=SYS_PTRACE \
-        --rm \
-        -e CC="/usr/bin/gcc-4.9" \
-        -e BAZEL_CXXOPTS="-std=${std}" \
-        ${DOCKER_EXTRA_ARGS:-} \
-        ${DOCKER_CONTAINER} \
-        /usr/local/bin/bazel test ... \
-          --compilation_mode="${compilation_mode}" \
-          --copt="${exceptions_mode}" \
-          --copt=-Werror \
-          --define="absl=1" \
-          --keep_going \
-          --show_timestamps \
-          --test_env="GTEST_INSTALL_FAILURE_SIGNAL_HANDLER=1" \
-          --test_env="TZDIR=/abseil-cpp/absl/time/internal/cctz/testdata/zoneinfo" \
-          --test_output=errors \
-          --test_tag_filters=-benchmark \
-          ${BAZEL_EXTRA_ARGS:-}
-    done
-  done
-done