Export of internal Abseil changes

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a9ea60e9c0ccd744b6f12fd021dbedfe826dfe84 by Matt Kulukundis <kfm@google.com>:

Add an internal hook to allow keeping flags in sync with global state.

Rollforward, except continue including hashtablez_flags.h in absl_flags.h so users don't break.

PiperOrigin-RevId: 412198044

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183e5c440b68c797ce4a82102f94f41c97a14674 by Martijn Vels <mvels@google.com>:

Internal cleanups and changes

PiperOrigin-RevId: 412083793

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3740faf7c5a2e1723e3c7e4d1b3f3db7cbec6e61 by Abseil Team <absl-team@google.com>:

Mark Cord::Clear() with the ABSL_ATTRIBUTE_REINITIALIZES attribute.

This prevents false positives in the clang-tidy check bugprone-use-after-move; it allows Clear() to be called on a moved-from Cord without any warnings, and the Cord will thereafter be regarded as initialized again.

PiperOrigin-RevId: 412082757

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a730d3f4ba06b55ae50386920a0544592069ac01 by Abseil Team <absl-team@google.com>:

StrJoin: Support iterators that do not have an `operator->`

Allows using `StrJoin` with iterators that do not have an `operator->`.
The `operator->` requirement for input iterators was dropped in C++20.

PiperOrigin-RevId: 412066130

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6773c0ced2caa6a7855898298faecc584f3997ec by Andy Soffer <asoffer@google.com>:

Rollback of internal hook for keeping flags in sync with global state.

PiperOrigin-RevId: 411895027

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4e7016a2fb88ce97853ef85ad5b4f76998eacca1 by Matt Kulukundis <kfm@google.com>:

Add an internal hook to allow keeping flags in sync with global state.

PiperOrigin-RevId: 411867376

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2a7d4056e467b6b5d8a7aa9398d6cb5454c10fc5 by Martijn Vels <mvels@google.com>:

Internal change

PiperOrigin-RevId: 411806932
GitOrigin-RevId: a9ea60e9c0ccd744b6f12fd021dbedfe826dfe84
Change-Id: Ib35bb7b40774979ed2ad205bbb1744b1085eae78
9 files changed
tree: 073a0920d0041551d0a6ecce37f90be1e4f45983
  1. .github/
  2. absl/
  3. ci/
  4. CMake/
  5. .clang-format
  6. .gitignore
  7. ABSEIL_ISSUE_TEMPLATE.md
  8. AUTHORS
  9. BUILD.bazel
  10. CMakeLists.txt
  11. conanfile.py
  12. CONTRIBUTING.md
  13. create_lts.py
  14. FAQ.md
  15. LICENSE
  16. README.md
  17. UPGRADES.md
  18. WORKSPACE
README.md

Abseil - C++ Common Libraries

The repository contains the Abseil C++ library code. Abseil is an open-source collection of C++ code (compliant to C++11) designed to augment the C++ standard library.

Table of Contents

About Abseil

Abseil is an open-source collection of C++ library code designed to augment the C++ standard library. The Abseil library code is collected from Google's own C++ code base, has been extensively tested and used in production, and is the same code we depend on in our daily coding lives.

In some cases, Abseil provides pieces missing from the C++ standard; in others, Abseil provides alternatives to the standard for special needs we've found through usage in the Google code base. We denote those cases clearly within the library code we provide you.

Abseil is not meant to be a competitor to the standard library; we've just found that many of these utilities serve a purpose within our code base, and we now want to provide those resources to the C++ community as a whole.

Quickstart

If you want to just get started, make sure you at least run through the Abseil Quickstart. The Quickstart contains information about setting up your development environment, downloading the Abseil code, running tests, and getting a simple binary working.

Building Abseil

Bazel and CMake are the official build systems for Abseil.

See the quickstart for more information on building Abseil using the Bazel build system.

If you require CMake support, please check the CMake build instructions and CMake Quickstart.

Support

Abseil is officially supported on many platforms. See the Abseil platform support guide for details on supported operating systems, compilers, CPUs, etc.

Codemap

Abseil contains the following C++ library components:

  • base Abseil Fundamentals
    The base library contains initialization code and other code which all other Abseil code depends on. Code within base may not depend on any other code (other than the C++ standard library).
  • algorithm
    The algorithm library contains additions to the C++ <algorithm> library and container-based versions of such algorithms.
  • cleanup
    The cleanup library contains the control-flow-construct-like type absl::Cleanup which is used for executing a callback on scope exit.
  • container
    The container library contains additional STL-style containers, including Abseil's unordered “Swiss table” containers.
  • debugging
    The debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities.
  • hash
    The hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil.
  • memory
    The memory library contains C++11-compatible versions of std::make_unique() and related memory management facilities.
  • meta
    The meta library contains C++11-compatible versions of type checks available within C++14 and C++17 versions of the C++ <type_traits> library.
  • numeric
    The numeric library contains C++11-compatible 128-bit integers.
  • profiling
    The profiling library contains utility code for profiling C++ entities. It is currently a private dependency of other Abseil libraries.
  • status
    The status contains abstractions for error handling, specifically absl::Status and absl::StatusOr<T>.
  • strings
    The strings library contains a variety of strings routines and utilities, including a C++11-compatible version of the C++17 std::string_view type.
  • synchronization
    The synchronization library contains concurrency primitives (Abseil's absl::Mutex class, an alternative to std::mutex) and a variety of synchronization abstractions.
  • time
    The time library contains abstractions for computing with absolute points in time, durations of time, and formatting and parsing time within time zones.
  • types
    The types library contains non-container utility types, like a C++11-compatible version of the C++17 std::optional type.
  • utility
    The utility library contains utility and helper code.

Releases

Abseil recommends users “live-at-head” (update to the latest commit from the master branch as often as possible). However, we realize this philosophy doesn't work for every project, so we also provide Long Term Support Releases to which we backport fixes for severe bugs. See our release management document for more details.

License

The Abseil C++ library is licensed under the terms of the Apache license. See LICENSE for more information.

Links

For more information about Abseil: