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abseil
abseil-cpp
C++2017–2026
abseil / abseil-cpp

abseil-cpp

Abseil Common Libraries (C++)

45Distinct people
62Mentions
1Explicit recommenders
18.2KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Abseil Common Libraries (C++)

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

I recommend Abseil. They have a good style that uses some modern C++ features but not the kitchen sink. Example you could start right here:…

jeffbee used a recommendation phrase. One indexed comment matches. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 11:23:53 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year62 dated mentions

Observed mentions: 2017-09-26 18:49:52 UTC to 2026-09-12 20:10:45 UTC.

02468102017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 4 mentions; 1 submissions, 3 comments20172018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 7 mentions; 0 submissions, 7 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 10 mentions; 0 submissions, 10 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 8 mentions; 0 submissions, 8 comments20212022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 10 mentions; 1 submissions, 9 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 6 mentions; 0 submissions, 6 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 6 mentions; 0 submissions, 6 comments2026-01-01 00:00:00 UTC to 2027-01-01 00:00:00 UTC (exclusive): 6 mentions; 1 submissions, 5 comments. Incomplete calendar period.2026*

* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC413
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC202
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC707
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC10010
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC808
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC303
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC1019
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC606
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC606
2026 (partial)2026-01-01 00:00:00 UTC2027-01-01 00:00:00 UTC615

From the project README

An excerpt from the repository, fetched Nov 13, 2026.

Read the project’s introduction
Abseil - C++ Common Libraries The repository contains the Abseil C++ library code. Abseil is an open-source collection of C++ code (compliant to C++17) designed to augment the C++ standard library. Table of Contents About Abseil Quickstart Building Abseil Support Codemap Releases License Links 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 follows Google's Foundational C++ Support Policy. See this table for a list of currently supported versions compilers, platforms, and build tools. Codemap Abseil contains the following C++ library components: base 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. crc The crc library contains code for computing error-detecting cyclic redundancy checks on data. debugging The debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities. flags The flags library contains code for handling command line flags for libraries and binaries built with Abseil. hash The hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil. log The log library contains LOG and CHECK macros and facilities for writing logged messages out to disk, stderr, or user-extensible destinations. memory The memory library contains memory management facilities that augment C++'s <memory> library. meta The meta library contains type checks similar to those available in the C++ <type_traits> library. numeric The numeric library contains 128-bit integer types as well as implementations of C++20's bitwise math functions. profiling The profiling library contains utility code for profiling C++ entities. It is currently a private dependency of other Abseil libraries. random The random library contains functions for generating pseudorandom values. status The status library contains abstractions for error handling, specifically absl::Status and absl::StatusOr<T>. strings The strings library contains a variety of strings routines and utilities. 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. 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: Consult our Abseil Introduction Read Why Adopt Abseil to understand our design philosophy. Peruse our Abseil Compatibility Guarantees to understand both what we promise to you, and what we expect of you in return.
Read the full README on GitHub

What Hacker News says

10 sources
What about something like https://github.com/abseil/abseil-cpp/blob/master/absl/string... ? ASCII lowercase can be something like auto is_upper= (x > '@') & (x < '['); return is_upper ? x+32 : x; Which boils down to add, add, cmp, cmov on x86. It might save some cache traffic, but the cache traffic is less code since it's only a mov. The version that's code instead of lookups probably exacerbates register pressure problems in large programs? I don't have good intuition for which would be more efficient in practice.
In You probably shouldn't use a lookup table (2022)
Is it possible that GPT-4 already had this new optimization somewhere in its training set? The optimizing patch DeepMind published on has been floating around for several months at this point… Edit: I found the merges for sorting (Jan 2022) [1] and hashing (Jan 2023) [2]. Both of these are very plausibly in the training set for GPT-4, which was frozen sometime in March 2023. [1] https://reviews.llvm.org/D118029 [2] https://github.com/abseil/abseil-cpp/commit/74eee2aff683cc7d...
In GPT-4 “discovered” the same sorting algorithm as AlphaDev by removing “mov S P”
You can see hashing optimizations as well https://www.deepmind.com/blog/alphadev-discovers-faster-sort..., https://github.com/abseil/abseil-cpp/commit/74eee2aff683cc7d... I was one of the members who reviewed expertly what has been done both in sorting and hashing. Overall it's more about assembly, finding missed compiler optimizations and balancing between correctness and distribution (in hashing in particular). It was not revolutionary in a sense it hasn't found completely new approaches but converged to something incomprehensible for humans but relatively good for performance which proves the point that optimal programs are very inhuman. Note that for instructions in sorting, removing them does not always lead to better performance, for example, instructions can run in parallel and the effect can be less profound. Benchmarks can lie an
Read the rest
d compiler could do something differently when recompiling the sort3 function which was changed. For hashing it was even funnier, very small strings up to 64 bit already used 3 instructions like add some constant -> multiply 64x64 -> xor upper/lower. For bigger ones the question becomes more complicated, that's why 9-16 was a better spot and it simplified from 2 multiplications to just one and a rotation. Distribution on real workloads was good, it almost passed smhasher and we decided it was good enough to try out in prod. We did not rollback as you can see from abseil :) But even given all that, it was fascinating to watch how this system was searching and was able to find particular programs can be further simplified. Kudos to everyone involved, it's a great incremental change that can bring more results in the future.
In Deepmind Alphadev: Faster sorting algorithms discovered using deep RL

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