| commit | 14b8a4eac3e5a7b97ba4cc7b7dadf2a85aae8215 | [log] [tgz] |
|---|---|---|
| author | Arthur O'Dwyer <arthur.j.odwyer@gmail.com> | Sat Feb 17 09:32:01 2024 -0800 |
| committer | Copybara-Service <copybara-worker@google.com> | Sat Feb 17 09:33:19 2024 -0800 |
| tree | 53e0c8bbe0041bd92e08ea44bf5e658e676d26cc | |
| parent | 8a3caf7dea955b513a6c1b572a2423c6b4213402 [diff] |
PR #1625: absl::is_trivially_relocatable now respects assignment operators Imported from GitHub PR https://github.com/abseil/abseil-cpp/pull/1625 Trivial relocatability also requires that the type not do anything weird with its assignment operator; update the type-trait to reflect this. (This is the definition used by BSL, Folly, HPX, Thrust, Parlay, Amadeus, and P1144.) This is important if we want to use `absl::is_trivially_relocatable` as a gate for memcpy optimizations in `inlined_vector::erase` and/or `inlined_vector::swap`, because in those cases relocation is used to replace part of a sequence involving assignment; the optimization requires an assignment operator that behaves value-semantically. Clang's builtin currently fails to check the assignment operator, so we stop using it entirely for now. We already refused to use it on Win32, Win64, and Apple, for various unrelated reasons. I'm working on giving Clang's builtin the behavior that would let us re-enable it here. Assume that any compiler providing both `__cpp_impl_trivially_relocatable` and a builtin `__is_trivially_relocatable(T)` will use the appropriate (P1144) definition for its builtin. Right now there's only one such compiler (the P1144 reference implementation, which forks Clang), so this is largely a moot point, but I'm being optimistic. Merge d943abdbabc1b7080aa5f0a2fff3e724135164dc into 34604d5b1f6ae14c65b3992478b59f7108051979 Merging this change closes #1625 COPYBARA_INTEGRATE_REVIEW=https://github.com/abseil/abseil-cpp/pull/1625 from Quuxplusone:trivially-relocatable d943abdbabc1b7080aa5f0a2fff3e724135164dc PiperOrigin-RevId: 607977323 Change-Id: I6436a60326c6d1064bdd71ec2e15b86b7a29efd4
The repository contains the Abseil C++ library code. Abseil is an open-source collection of C++ code (compliant to C++14) designed to augment the C++ standard library.
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.
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.
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.
Abseil follows Google's Foundational C++ Support Policy. See this table for a list of currently supported versions compilers, platforms, and build tools.
Abseil contains the following C++ library components:
base 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 algorithm library contains additions to the C++ <algorithm> library and container-based versions of such algorithms.cleanup cleanup library contains the control-flow-construct-like type absl::Cleanup which is used for executing a callback on scope exit.container container library contains additional STL-style containers, including Abseil's unordered “Swiss table” containers.crc The crc library contains code for computing error-detecting cyclic redundancy checks on data.debugging debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities.flags flags library contains code for handling command line flags for libraries and binaries built with Abseil.hash hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil.log log library contains LOG and CHECK macros and facilities for writing logged messages out to disk, stderr, or user-extensible destinations.memory memory library contains memory management facilities that augment C++'s <memory> library.meta meta library contains compatible versions of type checks available within C++14 and C++17 versions of the C++ <type_traits> library.numeric numeric library contains 128-bit integer types as well as implementations of C++20's bitwise math functions.profiling profiling library contains utility code for profiling C++ entities. It is currently a private dependency of other Abseil libraries.random random library contains functions for generating psuedorandom values.status status library contains abstractions for error handling, specifically absl::Status and absl::StatusOr<T>.strings strings library contains a variety of strings routines and utilities, including a C++14-compatible version of the C++17 std::string_view type.synchronization synchronization library contains concurrency primitives (Abseil's absl::Mutex class, an alternative to std::mutex) and a variety of synchronization abstractions.time time library contains abstractions for computing with absolute points in time, durations of time, and formatting and parsing time within time zones.types types library contains non-container utility types, like a C++14-compatible version of the C++17 std::optional type.utility utility library contains utility and helper code.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.
The Abseil C++ library is licensed under the terms of the Apache license. See LICENSE for more information.
For more information about Abseil: