May 2021 - Boost - lists.preview.boost.org

CMake Announcement from Boost Steering Committee
by Jon Kalb 13 Aug '24

13 Aug '24

The libraries produced by the Boost community have had a greater impact on the way that the C++ community writes code than any other library implementation. The focus of the Boost community will always be on the libraries, but it is undeniable that we are dependent on and often limited by the infrastructure of our trade. Years ago, the move to Git was contentious; yet, it was required to improve development. In a similar vein our build system has become an impediment for many developers and users, existing and prospective. Therefore, we, the Steering Committee, announce to the Boost community our desire and intent to move Boost’s build system to CMake for users and developers alike. We are soliciting comments and proposals from the community to guide the process and the goals. Our desire is that the community can come to consensus by the end of the calendar year with a vision of supporting users and developers. We understand that the actual process of achieving the end goal will be long, time consuming, and not without its share of conflict. We also recognize that the Boost community is comprised of bright and passionate individuals that are eager to get involved and help get work done. The members of the Steering Committee have been encouraged by the discussions and activity surrounding CMake on the mailing lists over the years and know that many people have voiced visions. We hope that each of you rejoins the discussion to support this initiative and contributes to the common goal of improving Boost’s integration into the broader C++ ecosystem. For the Boost Steering Committee, Jon Kalb, Chair jonkalb(a)boost.org

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Boost Governance?
by René Ferdinand Rivera Morell 09 Aug '24

09 Aug '24

A disclaimer: I write this solely as a Boost Library author. And not in any other capacity or representing any other interest. It's now been at least a year since Boost switched from the Software Freedom Conservancy to the Boost Foundation for its governance organization. But have people noticed any difference? Did you know that switch happened? Did you know that they held an election for the Board of Directors and for the Officers? Do you know when that election happened? Do you know who got elected? Do you know how they were selected? Do you know what their responsibilities are? Do you know what their bylaws are? Do you know their financials? More importantly: Did you answer "no" to any of those questions? As a library author, I can say I definitely answered no to many of those questions. This is a problem. As authors, without asking, we should know those answers from the organization that governs our work. We should have input into how that organization governs. In other words, we deserve open and transparent governance; not the closed and opaque status quo. -- -- René Ferdinand Rivera Morell -- Don't Assume Anything -- No Supone Nada -- Robot Dreams - http://robot-dreams.net

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Boost.Text is looking for a (mini-)review manager
by Zach Laine 07 Dec '22

07 Dec '22

I've made all the recommended changes to Boost.Text that came up in the review. Glen, the previous review manager, recommended a mini review of Boost.Text once I'd made those changes. If you'd like to manage the mini-review, please let me know. For everyone, including potential reviewers and review managers, here are the major changes: * All the specific review feedback issues have been addressed. * The string layer is now gone. * The text layer got a major re-work. It is now a set of template-based adaptors (basic_text<>, vs. a text typedef. etc.), which lets everyone get what they want. You can change the underlying storage type (including whatever allocator you prefer), select UTF-8 or UTF-16, and change the normalization form. Glen recommended I drop this layer, but the library is way less useful without this stuff, and these changes address all the concerns raised about the text layer in the review. The updated docs can be found here: https://tzlaine.github.io/text/doc/html/index.html Oh yeah, and I added concept constraints to the whole library when you build in C++20 mode. Zach

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[review][JSON] Review of JSON starts today: Sept 14 - Sept 23
by Pranam Lashkari 09 Aug '22

09 Aug '22

Boost formal review of Vinnie Falco and Krystian Stasiowski's library JSON starts today and will run for 10 days ending on 23 Sept 2020. Both of these authors have already developed a couple of libraries which are accepted in Boost(boost beast and Static String) This library focuses on a common and popular use-case for JSON. It provides a container to hold parsed and serialised JSON types. It provides more flexibility and better benchmark performance than its competitors. JSON highlights the following features in the documentation: - Fast compilation - Require only C++11 - Fast streaming parser and serializer - Easy and safe API with allocator support - Constant-time key lookup for objects - Options to allow non-standard JSON - Compile without Boost, define BOOST_JSON_STANDALONE - Optional header-only, without linking to a library (a point I would like to add in highlight: it has cool Jason logo 😝) To quickly understand and get the flavour of the library take a look at "Quick Look" <http://master.json.cpp.al/json/usage/quick_look.html> You can find the source code to be reviewed here: <https://github.com/CPPAlliance/json/tree/master> You can find the latest documentation here: <http://master.json.cpp.al/> Benchmarks are also given in the document which can be found here: <http://master.json.cpp.al/json/benchmarks.html> Some people have also given the early reviews, the thread can be found here: <https://lists.boost.org/Archives/boost/2020/09/249745.php> Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including JSON as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found here: <http://www.boost.org/community/reviews.html> Thank you for your effort in the Boost community. -- Thank you, Pranam Lashkari, https://lpranam.github.io/

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[container] Contributing 'stationary_vector' to Boost
by Mehrdad Niknami 13 Jun '22

13 Jun '22

Hi all, Happy new year! New mailing list member here. I've developed an STL-style stationary_vector class that retains elements in-place when growing. Very briefly, it is effectively a piecewise-contiguous vector, with the following advantages over vector: - Appending has O(1) overhead in the *worst* case (e.g., push_back() does not move elements) - Insertion and random-access can be done in parallel, as prior iterators & references remain valid This has a variety of benefits, including better UX (no "hiccups" due to reallocations), and the ability to simplify parallel processing of streaming data. It occurred to me the larger C++ community might find this useful. I was wondering if there would be interest in incorporating it into Boost.Container, and if so, what steps I could take to make that happen? I'm of course happy to discuss the design etc. with anyone who might be interested. Summary: https://github.com/mehrdadn/libvital/blob/master/doc/vital/container/statio… Implementation: https://github.com/mehrdadn/libvital/blob/master/include/vital/container/st… Thank you, Mehrdad

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Adding my sorting algorithm, ska_sort, to boost, attempt 2
by Malte Skarupke 24 Nov '21

24 Nov '21

Hi everyone, I started a discussion about this in October, but at the time the maintainer of the sort library was busy, then I was busy, so now it's January... I wrote a generalized version of radix sort a couple years ago and gave a talk about it here: https://www.youtube.com/watch?v=zqs87a_7zxw I would like to get a new version of that sorting algorithm into boost. It's faster than what I showed several years ago. It's also even more general and has a new interface that should be easier to extend. I uploaded the code here: https://github.com/skarupke/sort/tree/master The documentation is also already updated with new benchmark results. Let me know what's required to get this into boost. Would you like this in the form of a pull request? One of the big things that probably needs review is the interface, since radix sorting works differently than comparison based sorting. For most normal uses you just need to provide a sort key, but more complicated cases can get more complicated. I tried very hard to make everything easy, but I'd also be curious if others can come up with better ways of doing the interface. Thanks, Malte -- Malte Skarupke malteskarupke(a)fastmail.fm

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Adding CMakeLists.txt files
by Peter Dimov 31 May '21

31 May '21

I'm adding CMakeLists.txt files (mostly generated by `boostdep --cmake <libname>` to libraries that don't have one yet. Apologies (in advance) to all the maintainers for not going through the proper procedure, but this is much easier done in bulk (and order matters).

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Tool maintenance
by Edward Diener 27 May '21

27 May '21

There is a list of maintainers for Boost libraries at libs/maintainers.txt. Is there likewise a list of maintainers for Boost tools ? I have discovered a serious bug with BoostBook and nested namespaces, created an issue, but fear that no one will respond. I would like to e-mail anybody who is a maintainer for BoostBook who might be able to look at the issue and fix it, but there is no list of maintainers for Boost tools which I can find. The person who appears to have worked with BoostBook in the past, Daniel James, is no longer active with Boost so I have no idea who might be able to fix the issue.

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Develop Regression Tests Failing
by Tom Kent 26 May '21

26 May '21

Since sometime yesterday, all the gcc/clang develop runners I maintain (not sure about Visual Studio, that machine has been down for updates) have been failing, before the tests suite can even start running. Master still looks good. They end with the following: - bzip2 : yes [30] - lzma : yes [30] - zstd : no [30] - lzma : yes (cached) [30] - has_lzma_cputhreads builds : no [2] - auto_ptr : yes [3] error: Unable to find file or target named error: '/python//numpy' error: referred to from project at error: '../libs/python/build' I believe this is because of the python ( https://github.com/boostorg/python/pull/362) and build ( https://github.com/boostorg/build/pull/726) pull requests that were merged in around that time. The question is, why is this causing an issue....I have some vague memory of the regression test suite always using build from master? Am I remembering this correctly? If so, I think we may need to back out the python change until build's develop branch merges to master? I'm seeing this across multiple docker images, one that has been rather stable is this: https://hub.docker.com/layers/teeks99/boost-cpp-docker/clang-11/images/sha2… running with this user-config.jam: https://github.com/teeks99/boost-cpp-docker/blob/master/clang-11/user-confi… and numpy installed for both python 2 and 3. Thoughts? Tom

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[boostbook] Doxygen nested namespaces entities not being handled
by Edward Diener 20 May '21

20 May '21

I am seeing an issue where nested namespace doxygen documented entities are not being generated by BoostBook for the final documentation of a reference section in a library's documentation. I am using the quickbook -> boostbook -> html set of tools in the doc jamfile. If I just use doxygen directly to generate the documentation the nested namespace entities are there, so this appears to be a BoostBook problem. Has this problem always existed ? Has anyone else ever encountered it ? I first reported this as a Boost Build issue at https://github.com/bfgroup/b2/issues/18, but then reported this at https://github.com/boostorg/boostbook/issues/10.

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Re: [boost] Boost Governance?
by Glen Fernandes 18 May '21

18 May '21

Rene wrote: > It's now been at least a year since Boost switched from the Software Freedom Conservancy to the Boost Foundation for its governance organization. 13:14 <glenfe> @grafikrobot The Software Freedom Conservancy never governed the Boost C++ Libraries, nor did the Boost Steering committee, nor does the Boost Foundation. Only the Boost community does that. 13:15 <grafikrobot> Hopefully you'll clarify that on the dev list. i.e. The "Boost Steering Committee"[1] became "Boost Foundation"[2]. [1] https://sites.google.com/a/boost.org/steering/home [2] https://sites.google.com/a/boost.org/steering/boost-foundation It still deals with the C++Now conference, providing the mailing lists, hosting, etc. But any decision making and governance of the Boost libraries is still the domain of the Boost community (i.e. you, me, and the other Boost library authors and maintainers). Glen

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[sync] Optimizing Boost's sync using futex2
by André Almeida 15 May '21

15 May '21

Hi there, I'm the author of futex2[0], a WIP new set of Linux's syscalls that allows userspace to write efficient sync mechanisms. I would like to hear from Boost's developers if the project would benefit from this new interface. >From Boost/sync's codebase, I can see that you are already familiar with futexes, but just in case: * What's futex? futex stands for "fast userspace mutexes". It's a syscall that basically exposes a wait queue, where userspace can ask to put threads to sleep and to wake them. The index of such queue is an unsigned int address (that is usually called a futex). It's value doesn't mean anything for the kernel, userspace is responsible to defining the rules of it and implementing the logic. * Why futex2? futex has long standing issues that seems impossible to be solved in the current interface, so we are designing a new set of syscalls taking those problems in account (more on that at [0]). It's not merged yet, and I'm researching some uses cases to validate and get feedback about the API. The new API has the following new features: * Variable sized futexes (6, 16, 32 and 64 bits): we aren't restrict to only 32 bits anymore, and this can be used for decreasing memory usage or to wait on an address * Wait for multiple futexes: this function enables userspace to wait on a list of futexes and wake on the first that triggers a wake. Our current use case for this is for game engines and to emulate WaitForMultipleObjects from WinAPI in Wine * NUMA-awarenes: current futex has a single global hash table that is allocated in some node. Every futex() call that happens on the other nodes will have a access penalty. At futex2, there'll be a single table per node, so you can specify which one you want to operate on to increase locality. The detailed description of the API can be seen in the documentation patch[1]. Do you think that Boost would benefit from it? Thanks, André - futex2 talk at OpenSource Summit: https://www.youtube.com/watch?v=eG6GMBTcPQ8 [0] https://lore.kernel.org/lkml/20210427231248.220501-1-andrealmeid@collabora.… [1] https://lore.kernel.org/lkml/20210427231248.220501-7-andrealmeid@collabora.…

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Final Notice: BinTray is shutting down 1-May (that's SATURDAY)
by Marshall Clow 07 May '21

07 May '21

Bintray is “sunsetting” on the 1st of May. At that time, you will be unable to download boost releases from there. Before that time, their service will be occasionally interrupted. The web site has been updated, all the download links now refer to https://boostorg.jfrog.io/artifactory/main/release/ <https://boostorg.jfrog.io/artifactory/main/release/> Example: Instead of downloading from: https://dl.bintray.com/boostorg/release/1.76.0/source/boost_1_76_0.tar.gz <https://dl.bintray.com/boostorg/release/1.76.0/source/boost_1_76_0.tar.gz> You should download from: https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/boost_1_76… <https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/boost_1_76…> This applies to all releases from 1.63.0 onward (The pre-1.63 releases are still hosted at SourceForge) — Marshall

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[GSoC] - Boost.Multiprecision Quad Double
by Γιάννης Γονιδέλης 07 May '21

07 May '21

Hello! Christopher, Unfortunately, due to some urgent issues I won't be able to contribute during the summer. Thus, in case you have been considering picking me I would ask you to make a new choice. Apologies, Giannis

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Google Summer of Code 2021
by David Bellot 05 May '21

05 May '21

Hi Boost community, The mentors are now finalizing their selection of the students. Google has been very generous this year with the number of slots we were allocated and we are happy to say that we will again have a nice (and large) team of incredible students developing with us this summer (or winter if you're down under like me). Stay tuned because we will announce the list of projects very soon. Best regards, David

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[Math] Standalone beta release
by John Maddock 05 May '21

05 May '21

Just a heads up that Boost.Math now has a (beta) standalone release at https://github.com/boostorg/math/releases/tag/v1.76-standalone-beta We would very much appreciate any interested parties giving it a whirl and reporting back. With many thanks to Matt Borland and Nick Thompson for making this possible! Best, John Maddock. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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wrong result in complex pow
by Gero Peterhoff 03 May '21

03 May '21

Hello, the pow-function pow(scalar, complex) in boost/math/cstdfloat/cstdfloat_complex_std.hpp get wrong result. Current implementation: inline complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE> pow(const BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE& x, const complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>& a) { return std::exp(a * std::log(x)); } I think that's correct: inline complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE> pow(const BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE& x, const complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>& a) { return std::exp(a * std::log(complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>(x))); } regards Gero

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Cannot build 1.76.0 for Windows (wrong path to compiler)
by Andreas Tscharner 03 May '21

03 May '21

Hello World, I try, according to the "Get started guide" >bootstrap.bat in the main boost directory. I get an error, because "C:\Program Files(x86)" ... contains a space and is not double quoted. So I replace all set "B2_CXX=%CXX% ..." with set "B2_CXX="%CXX%" ..." in tools\build\src\engine\config_toolset.bat After that I have the following problem: D:\Projects\development\QUARTIS-related\boost>.\bootstrap.bat Building Boost.Build engine LOCALAPPDATA=C:\Users\ATs\AppData\Local Found with vswhere C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise Found with vswhere C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise Call_If_Exists "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\Tools\..\..\VC\Auxiliary\Build\vcvarsall.bat" AMD64 ********************************************************************** ** Visual Studio 2019 Developer Command Prompt v16.9.4 ** Copyright (c) 2021 Microsoft Corporation ********************************************************************** [vcvarsall.bat] Environment initialized for: 'x64' ### ### Using 'vc142' toolset. ### D:\Projects\development\QUARTIS-related\boost\tools\build\src\engine>"C:/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.27.29110/bin/Hostx64/x64/cl.exe" /nologo /MP /MT /TP /Feb2 /wd4996 /O2 /GL /EHsc -DNDEBUG builtins.cpp class.cpp command.cpp compile.cpp constants.cpp cwd.cpp debug.cpp debugger.cpp execcmd.cpp execnt.cpp filent.cpp filesys.cpp frames.cpp function.cpp glob.cpp hash.cpp hcache.cpp hdrmacro.cpp headers.cpp jam.cpp jamgram.cpp lists.cpp make.cpp make1.cpp md5.cpp mem.cpp modules.cpp native.cpp object.cpp option.cpp output.cpp parse.cpp pathnt.cpp pathsys.cpp regexp.cpp rules.cpp scan.cpp search.cpp jam_strings.cpp startup.cpp subst.cpp sysinfo.cpp timestamp.cpp variable.cpp w32_getreg.cpp modules/order.cpp modules/path.cpp modules/property-set.cpp modules/regex.cpp modules/sequence.cpp modules/set.cpp /link kernel32.lib advapi32.lib user32.lib Das System kann den angegebenen Pfad nicht finden. It tries to start "C:/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.27.29110/bin/Hostx64/x64/cl.exe". Unfortunately at my system, I don't have this path. I have C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Tools\MSVC\14.28.29910... Please note the different number after "MSVC" What is the problem? How can I fix this? TIA and best regards Andreas -- ("`-''-/").___..--''"`-._ `o_ o ) `-. ( ).`-.__.`) (_Y_.)' ._ ) `._ `. ``-..-' _..`--'_..-_/ /--'_.' .' (il).-'' (li).' ((!.-' Andreas Tscharner andy(a)stupidmail.ch ICQ-No. 14356454

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Persistent CI failures for old compilers
by Jeff Garland 02 May '21

02 May '21

On at least the clang 3.8 and gcc4.8 I'm seeing python errors block the CI from running correctly. Downloading/unpacking pip==20.3.4 Cannot fetch index base URL https://pypi.python.org/simple/ Could not find any downloads that satisfy the requirement pip==20.3.4 Which of course has nothing to do with the compiler. Here's an active change where the CI is running. https://github.com/boostorg/date_time/pull/192 So the question is -- are these two old and now unsupported? Is there some CI setup change I need? I'd like to stop having to override the CI obviously. Thanks, Jeff

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Re: [boost] C++Now 2021 -- Library in a Week: Boosting Boost
by Bjorn Reese 02 May '21

02 May '21

On 2021-05-01 00:55, Jeff Garland via Boost wrote: > Every year at the end of the session, I solicit ideas from the community > about what 'library' we should work on in the following year. One Boost.Tokenizer could do with a modernization. It generates a lot of code for even simple tokenizations, which makes it unsuitable for embedded devices. Some issues to consider: * Separate the browsing API from the conversion API. ** The browsing API should use string_view. ** The conversion API should use output buffers instead of returing a string. * Provide an API with narrow contracts * Provide a constexpr API.

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C++Now 2021 -- Library in a Week: Boosting Boost
by Jeff Garland 01 May '21

01 May '21

C++Now 2021 is next week. For those that have never been, every year we have a workshop session called Library in a Week. While the goal of the session might be obvious from the title, needless to say, final Boost libraries don't happen in a week. So, actually, the real underlying goal is to build boost community and discuss c++ library design with projects that don't conflict with attendees day jobs. Every year at the end of the session, I solicit ideas from the community about what 'library' we should work on in the following year. One consistent suggestion has been to work on boost community maintenance. With the conference all virtual this year, I think this is the year to do it. The goal will be to generate pull requests from new or even old boost participants to improve our code base. While I'm sure we could wander around the various libraries and find issues that need some work to generate pull requests, I'm posting this looking for suggestions from the bigger community. Note that this doesn't need to be exclusive to new code -- it can be documentation or tests. Are there particular libraries we should look at? Are there particular issues that someone would like a hand tackling? Are there some upgrades to newer c++ features that someone could jump in on? Thanks, Jeff

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