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which version works with openssl 3.0.5?
by David Frank 04 Sep '22

04 Sep '22

I'm currently using version 60, it failed to compile with openssl 3.0.5. So I need to upgrade to a version that works. Thanks.

2 1

How to build Boost with static ICU via Msys2 / mingw-w64 / gcc on Windows?
by crillion＠tiscali.it 03 Sep '22

03 Sep '22

Hello, I'm trying to build boost 1.80 on windows 10 with the icu provided with msys2 (my goal in particular is that boost locale will build using my installed version of icu). My build platform is msys2 with mingw-w64 / gcc 12.2. By launching pacman -Q on the msys2-msys shell I have seen that I have icu 71.1-2 : (...) glib2 2.72.2-2 gmp 6.2.1-2 gnupg 2.2.36-1 grep 1~3.0-3 gzip 1.12-2 heimdal-libs 7.7.0-3 icu 71.1-2 inetutils 1.9.4-5 info 6.8-4 less 590-2 (...) on my system I have msys2 installed in the following folder C:programsmsys64 and in C:programsmsys64mingw64 there are the following folders : bin etc include lib libexec sbin share ssl var x86_64-w64-mingw32 in the lib folder I have found that there are lib files like libicuio.a, libicudt.a and libicutest.a . I extracted boost and then I've given the usual sequence of commands from the normal cmd shell of windows : for creating b2 : bootstrap.bat gcc for the actual build of boost, I've made the following attempts : b2 --toolset=gcc address-model=64 -sICU_PATH=C:programsmsys64mingw64 b2 --toolset=gcc address-model=64 include=C:programsmsys64mingw64include library-path=C:programsmsys64mingw64lib b2 --toolset=gcc address-model=64 -sICU_PATH=C:programsmsys64mingw64 include=C:programsmsys64mingw64include library-path=C:programsmsys64mingw64lib but none of these works : the build process always writes in its initial phase : (...) has_lzma_cputhreads builds : yes [2] cxx11_decltype : yes [2] cxx11_basic_alignas : yes [2] iconv (libc) : no [2] iconv (separate) : yes [2] icu : no [2] icu (lib64) : no [2] native atomic int32 supported : yes [2] has message compiler : no [2] native syslog supported : no [2] (...) what am I supposed to do to let b2 see the ICU lib files that I have in my msys2 distribution ? Thanks, Marco Voucher MISE per P.IVA e PMI: fino a 2500€ per la Banda Ultralarga. https://casa.tiscali.it/promo/?u=https://promozioni.tiscali.it/voucher_busi…..

1 0

suspendable/resumable/prioritizable task dispatcher
by chris-boostusers＠stankevitz.com 31 Aug '22

31 Aug '22

Hi, Unfortunately I don't have the vocabulary needed to ask this question, but hopefully I'll learn it here. Does Boost have something that will help me with this problem: I have a list of CPU-bound tasks I need to perform. I'll list two of them here: a) compute first zillion digits of pi (low priority) b) add two plus two (high priority) I co_spawn (a). Later, while (a) is running, I co_spawn (b). (a) will be suspended at a "co_suspension_point" so that (b) can take over. Of course when (b) completes, (a) will resume. For bonus points, it will support multiple threads (probably easy) and a task's priority can change over time (probably hard). Thank you! Chris PS: I was recently blown away by the coroutine capability of ASIO: Talking Async Ep1: Why C++20 is the Awesomest Language for Network Programming https://www.youtube.com/watch?v=icgnqFM-aY4

3 3

memory fault when passing var to a coroutine
by Piotr Gosławski 23 Aug '22

23 Aug '22

Hello, Using GCC 10.1 and Boost 1.77 I get a mem fault when executing the following code: #include <iostream> #include <boost/asio.hpp> #include <boost/asio/awaitable.hpp> struct TestStruct { std::string strField; }; boost::asio::awaitable<bool> TestFunction(TestStruct param) { std::cout << param.strField << std::endl; co_return true; } boost::asio::awaitable<void> TestCoroutine() { // This causes mem issue co_await TestFunction(TestStruct{"some string"}); } int main() { boost::asio::io_context io_context; boost::asio::co_spawn( io_context, []() { return TestCoroutine(); }, boost::asio::detached); io_context.run(); return 0; } Also tested with GCC 12.1 and Boost 1.79 - the result is the same ( https://godbolt.org/z/69MKbz7qE) Works if I use a temp variable: boost::asio::awaitable<void> TestCoroutine() { auto testStruct = TestStruct{"some string"}; co_await TestFunction(testStruct); } Or if I add a constructor to test struct: struct TestStruct { explicit TestStruct(const std::string& str) : strField(str) {} std::string strField; }; boost::asio::awaitable<void> TestCoroutine() { co_await TestFunction(TestStruct("some string")); } Is there any coroutines rule that I am violating here? If yes - is there any compiler option I can use to get a warning / error message? Full code with cmake can be found here: https://github.com/piotrgoslawski/mem_issue Thank you

1 0

re：question about compile the boost head file.
by zyx_xzy＠sina.com 23 Aug '22

23 Aug '22

Respeced Mr.Emil, Thank you for your kindly reply. >I can't reproduce this with msvc versions available on godbolt: >https://godbolt.org/z/E8vYWTPf6 Exactly on godbolt,the compilers work well. I test this by myself. Once again, I change to the Microsoft Visual Studio Community 2019 ver. 16.11.18. And compile the program ,the error still exist. >Can you provide a complete error log, including source file and line of the >error? soruce file:info.hppsource code line no:145soruce code:error_info_container_impl * c=new error_info_container_impl;error log:C2259 “boost::exception_detail::error_info_container_impl”: cannot instantiate abstract class, test_boost D:\boost_1_79_0\boost\exception\info.hpp 145 Best regards, zhiyong

2 1

question about compile the boost head file.
by zyx_xzy＠sina.com 20 Aug '22

20 Aug '22

hi anybody, I meet a problem when I try to compile the following program. #include <boost\exception\info.hpp> void main() { return; } The compile environment is Microsoft Visual Studio Community 2022 (64 位) - ver. 17.2.6.Compile error information is that C2259 “boost::exception_detail::error_info_container_impl”: cannot instantiate abstract class.I try many Boost versions,e.g.,boost 79,boost 65,boost64,boost60. They all give errors. Anybody can give me some suggestions? Best regards, zhiyong --------------------------------

2 1

Abwesenheitsnachricht: question about compile the boost head file.
by Sören Textor 20 Aug '22

20 Aug '22

Derzeit bin ich nicht im Hause Ihre E-Mail wird nicht weitergeleitet. In dringenden Fällen bitte support(a)ditec-gmbh.de oder Telefonhotline +49-6221-31698-110 oder die Zentrale +49-6221-31698-0 kontaktieren. ----------------------------------------------- DiTEC Dr. Siegfried Kahlich & Dierk Langer GmbH Im Breitspiel 19 | 69126 Heidelberg | Germany Handelsregister | Mannheim | HRB 341229 Dieses Dokument ist vertraulich zu behandeln. Die Weitergabe, sowie Vervielfältigung, Verwertung und Mitteilung seines Inhalts ist nur mit unserer ausdrücklichen Genehmigung gestattet. Alle Rechte vorbehalten, insbesondere für den Fall der Schutzrechtsanmeldung. This document has to be treated confidentially. Its contents are not to be passed on, duplicated, exploited or disclosed without our express permission. All rights reserved, especially the right to apply for protective rights.

1 0

[Boost.GIL] GCC 12.1.1 fails to compile boost.gil examples with -std=c++20
by B Aleck 18 Aug '22

18 Aug '22

Source: https://www.boost.org/doc/libs/1_80_0/libs/gil/doc/html/_downloads/resize.c… Compile with: g++ -std=c++20 -c gcc version: 12.1.1 The compile successes with -std=c++14 and -std=c++17, only fails with -std=c++20 Same error does not occur on clang Is this a boost bug or gcc bug?

2 1

Enumerating network interfaces and querying their properties
by Kenneth Porter 14 Aug '22

14 Aug '22

Is there a portable way to enumerate network interfaces and query their properties? I don't see anything in ASIO for that. Any recommendations for other libraries? So far the closest I've come is Python's netifaces library. (Maybe someone would like to fork the Python library's C source and bring it into Boost?) <https://github.com/al45tair/netifaces> I've got an app that configures a remote IoT device on the same segment and then opens UDP listeners to listen for a stream of data from the device. The user specifies the hostname or address of the device. I'd like to be able to restrict the listeners to just the interface that the device is connected to. I have two interfaces, one for the LAN and one for devices, and I don't want to listen on the LAN interface. So ideally I'd get the list of interfaces and their addresses and netmasks. I think I also need the routing table. I can then identify which interface will receive the incoming UDP stream.

1 0

Boost support for Arm64/Windows
by Jonathon Penix 12 Aug '22

12 Aug '22

Hi, I am interested in using Boost as a dependency on the Arm64/Windows platform but have been struggling to find information about the status for Boost libraries in general for Arm64/Windows. I am aware of a few specific libraries that directly mention their support status for Arm64/Windows (Boost.Atomic and Boost.Context, for example) or have had Arm64 related patches in their release notes (Boost.Build, for example). Are there any public boards/trackers for the current Boost status or outstanding issues for Boost on Arm64/Windows that I may have missed? Or should platform support be generally assumed to work outside of specific cases like Boost.Context so long as a conformant compiler is provided for the platform? Thanks!

2 1

[release] Boost 1.80.0
by Glen Fernandes 11 Aug '22

11 Aug '22

Release 1.80.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.80.0> You can also download directly from: <https://boostorg.jfrog.io/artifactory/main/release/1.80.0/> To install this release on your system, see <http://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. -- The Boost Release Team Marshall Clow, Glen Fernandes, Michael Caisse

3 2

Broken link to latest code from old ASIO example
by Kenneth Porter 11 Aug '22

11 Aug '22

The directory structure of ASIO changed a bit and now the website pages of samples in old versions no longer direct to the correct page in the latest version: <https://www.boost.org/doc/libs/1_51_0/doc/html/boost_asio/example/icmp/ping…> I wanted to see how to code a ping so I googled for "boost asio ping" and the top result was for 1.51.0. (I never get the latest code, but I can always jump to an older version and then jump from there to the latest. It just didn't work this time.) It did work for 1.67.0 (later in the google search results) which led to the current page: <https://www.boost.org/doc/libs/1_79_0/doc/html/boost_asio/example/cpp03/icm…>

1 0

Fwd: [boost] Upcoming Boost.URL review
by Mateusz Loskot 06 Aug '22

06 Aug '22

---------- Forwarded message --------- From: Klemens Morgenstern via Boost <boost(a)lists.boost.org> Date: Sat, 6 Aug 2022, 15:30 Subject: [boost] Upcoming Boost.URL review To: <boost(a)lists.boost.org> Cc: Klemens Morgenstern <klemensdavidmorgenstern(a)gmail.com> This is a reminder that the boost.url review will start in a week on the 13th. The source code can be found here https://github.com/CPPAlliance/url and the documentation here https://master.url.cpp.al/ . I am looking forward to plenty of reviews. _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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Boost.Graph: user survey
by Jeremy Murphy 05 Aug '22

05 Aug '22

Dear Boost.Graph users, I'd like to know how you use Boost.Graph. If you know someone that uses Boost.Graph but is not on this mailing list, please forward this survey to them. The purpose of this survey is to help prioritize work on the areas of Boost.Graph that will have the most benefit to the users. I was planning to make a very sophisticated Google Forms survey, but that is so time consuming. These questions should all be taken in the context of using Boost.Graph. - Which operating systems do you use? - Which toolchains do you use? - What is the minimum C++ standard that you require support for? (e.g. 03, 11, 14, etc) - Which features of Boost.Graph are you using? - Which features do you think Boost.Graph is missing? - What are the biggest problems with using Boost.Graph? Purely out of curiosity: - What do you use it for? - If you use it in business (or research), how critical is it? Thanks! Jeremy

4 5

Help with a compilation error [Boost/Math]
by Peder Lon Hauge 04 Aug '22

04 Aug '22

Hi, I'm trying to use Boost in order to find values of a 2F3 hypergeometric function. Just to check that I am using the package the correct way, I tried to compile the small test file below (using the example from the pFq docs), with the command $ g++ -o test.exe test.cpp -I /home/peder/boost/boost_1_79_0 As far as I understand, the library is header-only, so I didn't expect the compilation error below. I don't where I've made a mistake, and I'd greatly appreciate any help with figuring out the error. I'm running Ubuntu 20.04.04 on WSL and using gcc 9.4.0. Best regards, Peder Test program: #include <iostream> #include <boost/math/special_functions/hypergeometric_pFq.hpp> int main() { double z = -9; double h = boost::math::hypergeometric_pFq({2,3,4}, {5,6,7,8}, z); // Calculate 3F4 std::cout << h << std::endl; return 0; } Error message: $ g++ -o test.exe test.cpp -I /home/peder/boost/boost_1_79_0 /usr/bin/ld: /tmp/ccp4Lm8m.o: in function `std::pair<long double, long double> boost::math::detail::hypergeometric_pFq_checked_series_impl<std::initializer_list<int>, long double, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy>, boost::math::detail::iteration_terminator>(std::initializer_list<int> const&, std::initializer_list<int> const&, long double const&, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> const&, boost::math::detail::iteration_terminator const&, long long&)': test.cpp:(.text._ZN5boost4math6detail38hypergeometric_pFq_checked_series_implISt16initializer_listIiEeNS0_8policies6policyINS5_14default_policyES7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_EENS1_20iteration_terminatorEEESt4pairIT0_SB_ERKT_SF_RKSB_RKT1_RKT2_Rx[_ZN5boost4math6detail38hypergeometric_pFq_checked_series_implISt16initializer_listIiEeNS0_8policies6policyINS5_14default_policyES7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_EENS1_20iteration_terminatorEEESt4pairIT0_SB_ERKT_SF_RKSB_RKT1_RKT2_Rx]+0xeef): undefined reference to `boost::math::tools::promote_args<long double, float, float, float, float, float>::type boost::math::lgamma<long double, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> >(long double, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> const&)' /usr/bin/ld: test.cpp:(.text._ZN5boost4math6detail38hypergeometric_pFq_checked_series_implISt16initializer_listIiEeNS0_8policies6policyINS5_14default_policyES7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_EENS1_20iteration_terminatorEEESt4pairIT0_SB_ERKT_SF_RKSB_RKT1_RKT2_Rx[_ZN5boost4math6detail38hypergeometric_pFq_checked_series_implISt16initializer_listIiEeNS0_8policies6policyINS5_14default_policyES7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_S7_EENS1_20iteration_terminatorEEESt4pairIT0_SB_ERKT_SF_RKSB_RKT1_RKT2_Rx]+0xfe5): undefined reference to `boost::math::tools::promote_args<long double, float, float, float, float, float>::type boost::math::expm1<long double, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> >(long double, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> const&)' /usr/bin/ld: /tmp/ccp4Lm8m.o: in function `int boost::math::detail::log_pochhammer<int, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> >(int, unsigned int, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy>, int*)': test.cpp:(.text._ZN5boost4math6detail14log_pochhammerIiNS0_8policies6policyINS3_14default_policyES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_EEEET_S7_jT0_Pi[_ZN5boost4math6detail14log_pochhammerIiNS0_8policies6policyINS3_14default_policyES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_EEEET_S7_jT0_Pi]+0x3d): undefined reference to `boost::math::tools::promote_args<int, float, float, float, float, float>::type boost::math::lgamma<int, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> >(int, int*, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> const&)' /usr/bin/ld: test.cpp:(.text._ZN5boost4math6detail14log_pochhammerIiNS0_8policies6policyINS3_14default_policyES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_EEEET_S7_jT0_Pi[_ZN5boost4math6detail14log_pochhammerIiNS0_8policies6policyINS3_14default_policyES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_EEEET_S7_jT0_Pi]+0x57): undefined reference to `boost::math::tools::promote_args<int, float, float, float, float, float>::type boost::math::lgamma<int, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> >(int, int*, boost::math::policies::policy<boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy, boost::math::policies::default_policy> const&)' collect2: error: ld returned 1 exit status

3 3

[Query] Does boost support concurrent hash map, for ip fragment reassemble
by Jiany Wu 02 Aug '22

02 Aug '22

Hello, I want to use boost concurrent hash map to do fragment reassemble, does it support concurrent hash map? Or is there any similar concurrent data structure, which can support it? Thanks in advance! Best regards Dave

1 0

sgn/sign-function
by Gero Peterhoff 31 Jul '22

31 Jul '22

Hi John, i think your sign-function (boost/math/special_functions/sign.hpp) is incomplete. Because the resulttype is int, not all cases can be covered correctly (nan, inf, -0). With my implementation this works and it follows the std-conventions (sgn(FP) -> FP, sgn(INT/BOOL) -> double). I also tried to optimize them (branch-free, vectorizable). sgn(FP) -> FP ±0/±1 sgn(FP nan/inf) -> FP nan/inf sgn(INT) -> double +0/±1 sgn(UINT/BOOL) -> double +0/+1 regards Gero

1 0

C++11 or C++14?
by Vinnie Falco 29 Jul '22

29 Jul '22

I'm considering bumping up the C++ language requirement for Boost.URL from C++11 to C++14. I have concerns about doing this, because it affects all my downstream libraries (HTTP.Proto, HTTP.IO, Websocket.Proto, Websocket.IO, and any examples or complete clients/servers that I write). My main fear is that there are still a considerable number of individuals or corporations who, for whatever reason, cannot build with -std=c++14 or later despite having access to newer compilers. I don't mind if there is a small percentage of loss but I do mind if 20% or more of potential users will be locked out. The questions are: 1. Would you or your company be prevented from using Boost.URL if it required C++14? 2. Do you know any other organizations who cannot use C++14 or later? 3. Do you know of any regional or global metrics on who _cannot_ use libraries which require C++14? See also, this reddit thread on r/cpp: <https://www.reddit.com/r/cpp/comments/w6zuo5/c11_or_require_c14/> -- Regards, Vinnie Follow me on GitHub: https://github.com/vinniefalco

6 6

gcc 12 and clang 14
by Matt Hurd 28 Jul '22

28 Jul '22

Curious as to if gcc-12 and clang-14 may make it to the release compiler list for 1.80? (https://www.boost.org/users/history/version_1_80_0.html) Is that just a formality? I see the regression tests for both look in pretty good shape: https://www.boost.org/development/tests/develop/developer/summary.html Thanks all for your great work. Much appreciated, --Matt _______________ matthurd(a)acm.org

1 0

boost::asio::ssl::context::use_certificate_chain_file and boost::asio::ssl::context::use_certificate_file Methods Give "bad method" Error
by Osman Zakir 21 Jul '22

21 Jul '22

Hello. Message for update to previously-reported issue. It turns out that the "bad method" error was because of the boost::asio::ssl::context object methods I mentioned in the subject of this email. Reading the certs in from the files into std::strings manually and using use_certificate and use_certificate_chain instead is better, at least from what I saw. I still have an error in the browser (code: ERR_SSL_PROTOCOL_ERROR) when I try to visit my running app saying that the connection for the site isn't secure and that it gave back an invalid response. And running the command openssl s_client -connect <ip_address>:5501 -servername dragonosman.dynu.net gave this result: CONNECTED(00000148) 11784:error:1409442E:SSL routines:ssl3_read_bytes:tlsv1 alert protocol version:ssl\record\rec_layer_s3.c:1544:SSL alert number 70 --- no peer certificate available --- No client certificate CA names sent --- SSL handshake has read 7 bytes and written 322 bytes Verification: OK --- New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE No ALPN negotiated Early data was not sent Verify return code: 0 (ok) and when command exits, I see this error in my server console window: Lines 625 and 626: handshake: unsupported protocol (SSL routines, tls_early_post_process_client_hello) Lines 646 and 647: read: unspecified system error I'm assuming this is a HTTP/2 upgrade request inside a TLS ClientHello message, but is that enough reason for the SSL error I'm getting in my browser? Anyway, I've sent an email on the OpenSSL users mailing list to ask how to parse the ClientHello message, so hopefully I'll get something from there.

1 0

[container] flat_set using a reversed small_vector
by Phil Endecott 20 Jul '22

20 Jul '22

Dear Experts, I currently have: template <typename KEY, typename VALUE, size_t SZ> using small_flat_map = boost::container::flat_map< KEY, VALUE, std::less<KEY>, boost::container::small_vector< std::pair<KEY,VALUE>, SZ > >; This works OK, but one thing that I do with it quite often is auto i = m.upper_bound(...); m.erase(m.begin(),i); Erasing items at the start of the vector is of course the worst thing you can do for performance with a flat_map. So I was wondering if I can have a flat_map that stores its elements in the reverse order in the underlying vector. Question: can anyone think of a way to do this that doesn't require changing all of the downstream code? For a few milliseconds I thought I could just change std::less for std::greater but that reverses the externally-visible behaviour. Is there some Boost utility that can wrap the implementation vector to work in reverse? Thanks, Phil.

1 0

Server App using Boost.Beast, Sending Only One Certificate out of Chain
by Osman Zakir 16 Jul '22

16 Jul '22

Hi, everyone. I upgraded my server app to Boost 1.79.0 and tried running it, but there are issues: 1. I renewed my Let's Encrypt certs, but when I try to check them, I see it's only sending one cert out of a chain of three. And I'm loading the certs and the RSA private key using the SSL context methods to load the cert chain and key from files, too. 2. The read operation on line 640 in the do_session function in currency_converter.cpp gave a "bad method" error before, but mostly gives "the connection was forcibly closed by the remote host" error. I have the source code on GitHub here: https://github.com/DragonOsman/currency_converter.

1 0

[release] Boost 1.80.0 beta 1 released
by Glen Fernandes 14 Jul '22

14 Jul '22

Boost release 1.80.0 beta 1 is now available at: https://boostorg.jfrog.io/artifactory/main/beta/1.80.0.beta1/source/ The SHA256 checksums are: boost_1_80_0_b1.tar.bz2 - b29191c1bd4504511f9b1155c6f79f06cc7044444780392ed7358f5778ac7d16 boost_1_80_0_b1.tar.gz - ad3df9f63acd667dcf13375fa0e90e7303f851251e91d1505974bdbbf1f94907 boost_1_80_0_b1.7z - 7bfdf705b1d058c3525be90ed5cb47aacf919cd74aa7d5752d55e78aa60880ba boost_1_80_0_b1.zip - 1b509ed848f153086984658d4d4a57af6230f496a53bf88aba805bb49039012d Release notes (still need updates): https://www.boost.org/users/history/version_1_80_0.html Please try the beta and report any problems you encounter. Thanks, -- Boost Release Team

1 0

Higher than expected memory usage by boost::iostreams::gzip_compressor
by Alex Petty 13 Jul '22

13 Jul '22

Hello, I'm looking at adopting boost::iostreams for reading/writing compressed streams. I'm testing with textual files commonly on the order of a couple of GB uncompressed, and a couple hundred MB compressed. I noticed during some initial testing that using a gzip_compressor to write a compressed stream through boost::iostreams results in significant memory usage, I'm seeing hundreds of MB per compressed stream. It looks like internally the gzip_compressor must be doing some GC-type behavior, because I see its memory usage increase to just under 1GB per stream with a gzip_compressor, and then decrease again. Is there any way to control the memory that gzip_compressor is using? I've tried both increasing and decreasing the buffer size when gzip_compressor is constructed, but that buffer is tiny and cannot be what's driving the increased memory usage. Thanks, Alex

1 0

[Graph] Can users on Xcode 7-10 help out?
by Jeremy Murphy 12 Jul '22

12 Jul '22

Dear Boost.Graph users, Is anyone that uses old Xcode 7-10 able to help out with some curious compilation errors? https://github.com/boostorg/graph/issues/298 We'll do our best to fix them but I assume it might be easier for someone that actually uses these particular platforms. Thanks, cheers. Jeremy

1 0

xpressive: How to combine vector of regex to one?
by Anton Sergunov 08 Jul '22

08 Jul '22

Hello Boost Users! I'm seeking some help from the community because can't see answer in documentation or in source code. I need to find which regex of N my string matches. I don't like to compare them one by one, to speed up the process. It's easy to implement if I have them compile time: ```cpp sregex re = (s1 = re1)|(s2 = re2)|(s3=re3); ... std::set<int> foo(const std::string& str) { std::set<int> result; smatch match; if(regex_match(str, match, re)) { for(int i = 0; i<3; ++i) if(match[i+1]) result.insert(i); } return result; } ``` But I have a vector: ```cpp std::set<int> foo(const std::string& str, const std::vector<sregex>& reVector) { sregex re; int index = 1; for(auto&& item : reVector) { re |= (mark_tag(index++) = item); // (1) } std::set<int> result; smatch match; if(regex_match(str, match, re)) { for(int i = 0; i<reVector; ++i) if(match[i+1]) result.insert(i); } } return result; } ``` There at (1) `|=` doesn't work as I expect for some reson, It didn't catch some values. If I replace it with ```cpp re = re | (mark_tag(index++) = item); ``` it just crashes. If I replace with: ```cpp auto t = re; re = t | (mark_tag(index++) = item); ``` it making captures of previous tags to be subexpresions matches. So code doesn't work as I want. Is it any way to prevent sub-expression capture isolation? As I understand it should be some intermediate type before sregex to express expression under construction. So it will not isolate matches of existing part. I'm using v1.65.1 https://github.com/boostorg/xpressive/issues/24

1 0

Embedded install paths in CMake files for Boost 1.79
by Alex 05 Jul '22

05 Jul '22

Apologies if this is the wrong list. I tried boost-build but I'm not sure if my message was verified (I don't see it in the archive). I'm trying to make a build of Boost that includes the generated CMake files. For my case, I need to install the files to a staging area before packaging them up for installation in the target environment. I've tried "b2 --stagedir <dir> stage" but the generated CMake files still include the stagedir path in them, instead of the install prefix specified during bootstrap, which triggers errors in the packaging system I need to use. I'm also not sure if it's then possible to just install the headers to the same staging location. Is there a way to install to a staging location while the CMake files have the paths to the final install location? CMake uses CMAKE_STAGING_PREFIX for this but I can't find an equivalent for b2. I guess it must be required for cross-compiling though, if you want to support CMake on the target? Regards, Alex

1 0

Excessive dynamic allocation when using boost::split(..., boost::is_any_of(", "))?
by Dominique Pellé 05 Jul '22

05 Jul '22

Hi This following program shows many allocations coming from boost::split(..., boost::is_any_of(",")): ``` $ cat split.cpp #include <string> #include <cstdio> #include <boost/algorithm/string.hpp> #include <boost/container/small_vector.hpp> int main() { std::string str = "foo,bar,foobar,quux"; std::size_t s = 0; for (int i = 0; i < 100; ++i) { boost::container::small_vector<std::string, 4> v; #ifdef USE_IS_ANY_OF boost::split(v, str, boost::is_any_of(",")); #else boost::split(v, str, [](const char c) { return c == ',';}); #endif s += v.size(); } fprintf(stderr, "%zu\n", s); } ``` When using boost::is_any_of(","), there are 7 dynamic allocations per loop iteration whereas when using the lambda predicate, there are 0 dynamic allocation per loop as shown below: ``` $ clang++ -std=c++14 -DUSE_IS_ANY_OF split.cpp $ heaptrack ./a.out ... allocations: 702 $ clang++ -std=c++14 split.cpp $ heaptrack ./a.out ... allocations: 2 ``` I suspect that there are potential optimizations in Boost here to avoid so many allocations when boost::is_any_of(",") is used. Regards Dominique

3 2

Boost.URL review planned for 13-22 August 2022
by Mateusz Loskot 29 Jun '22

29 Jun '22

Folks, Klemens Morgenstern kindly volunteered [1] as the Review Manager (thanks Klemens!) for the Boost.URL [2], so we have planned the review shortly after the upcoming release of the Boost 1.80. Check the Review Schedule [3] for details! [1] https://lists.boost.org/Archives/boost/2022/06/253225.php [2] https://lists.boost.org/Archives/boost/2022/04/252814.php [3] https://www.boost.org/community/review_schedule.html Best regards, -- The Boost Review Wizards Mateusz Loskot

2 2

Boost Twitter is Blowing Up!!!
by Vinnie Falco 21 Jun '22

21 Jun '22

Greetings fellow users, library authors, maintainers, review wizards, release wizards, and Boost Foundation Board members! As part of our ongoing effort to continue the revitalization of Boost, a handful of us have taken the reins to post about Boost on social media. We have postings on Reddit and Hacker news, blog posts about the new efforts in Boost.Unordered, and new tweets. However, we could use your help! Right now the Boost Twitter account has a measly 957 followers. It would be great to increase our reach, so I'm asking everyone if they could be so kind as to Follow the official Boost Twitter account here: <https://twitter.com/Boost_Libraries> and then amplify our messages by Liking and Retweeting. Starting with this pinned tweet, which everyone will see when they visit the Boost Libraries Twittter profile page: <https://twitter.com/Boost_Libraries/status/1539003321939202048> Following the Boost Twitter account will give you up-to-date information about what is going on with Boost, including articles and mentions on other social media sites. Here is what we have so far: <https://www.reddit.com/r/cpp/comments/vfdcrz/advancing_the_state_of_the_art…> <https://www.reddit.com/r/cpp/comments/vbdr3z/new_boostunordered_containers_…> <https://twitter.com/hackernewstop10/status/1538622706035343364> <https://news.ycombinator.com/item?id=31801814> To summarize, engaging with Boost related content on social media will enhance our profile - any help is appreciated! -- Regards, Vinnie Follow me on GitHub: https://github.com/vinniefalco

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[JSON] Vote for Boost.JSON in this poll!
by Vinnie Falco 21 Jun '22

21 Jun '22

There's an online poll asking about which JSON library you use. If you use Boost.JSON consider voting for it: <https://meetingcpp.com/mcpp/survey/?q=2> Also, consider voting for it if you _don't_ use Boost.JSON, but you want to. -- Regards, Vinnie Follow me on GitHub: https://github.com/vinniefalco

1 0

[Locale] IBM437 encoding not supported in wconv
by Arnold, Stefan 14 Jun '22

14 Jun '22

Why is the IBM437 encoding not supported in boost::locale with the Win32 API ("wconv") backend? The following call will fail with a boost::locale::conv::invalid_charset_error when using the Win32 API backend: boost::locale::conv::to_utf<char>("abc", "IBM437") This is because "ibm437" is not contained in the all_windows_encodings variable in wconv_codepage.ipp (nor is "cp437" or another alias). As per Win32 API documentation (https://docs.microsoft.com/en-us/windows/win32/api/stringapiset/nf-stringap…, https://docs.microsoft.com/en-us/windows/win32/intl/code-page-identifiers) this encoding is supported in Win32 API. Furthermore, IBM437 is the legacy encoding of filenames in ZIP files, so it should be quite common.

1 1

Any objections to making C++14 the current baseline for Boost support and testing?
by John Maddock 10 Jun '22

10 Jun '22

Pursuant of discussion elsewhere: Does anyone have any concrete objections to Boost moving to a C++14 baseline? This would mean: * Library authors can drop and remove all support for pre-C++14 compilers after a suitable deprecation notice in place for say 3 releases. * The community maintenance team can likewise drop pre-C++14 support from community maintained / orphan libaries. * CI tests no longer need report pre-C++14 results. * From the next release onward, the boost super-project should clearly announce in our release notes, that C++11 and earlier support may no longer be available from the start of 2023. Thoughts? Thanks, John Maddock.

8 11

[thread] attribute constructor failing to compile
by Jeanette C. 07 Jun '22

07 Jun '22

Hey hey, using boost 1.78 from the Archlinux repository, using the thread constructor with boost::thread::attributes as first argument fails to compile. The relevant code from the small test program is this: void work(bool& done) // simple main function for the thread int main() { bool done = false; boost::thread::attributes attr; // all changes commented out in the program boost::thread th1(attr, work, std::ref(done)); // some code, sleep and set done to true th1.join(); return 0; } g++ 11.2.0 reports the following error: In file included from /usr/include/boost/thread/detail/thread.hpp:33, from /usr/include/boost/thread/thread_only.hpp:22, from /usr/include/boost/thread/thread.hpp:12, from thread_prio.cpp:1: /usr/include/boost/bind/bind.hpp: In instantiation of 'void boost::_bi::list2<A1, A2>::operator()(boost::_bi::type<void>, F&, A&, int) [with F = boost::thread_attributes; A = boost::_bi::list0; A1 = boost::_bi::value<int (*)(bool&)>; A2 = boost::_bi::value<std::reference_wrapper<bool> >]': /usr/include/boost/bind/bind.hpp:1273:18: required from 'boost::_bi::bind_t<R, F, L>::result_type boost::_bi::bind_t<R, F, L>::operator()() [with R = void; F = boost::thread_attributes; L = boost::_bi::list2<boost::_bi::value<int (*)(bool&)>, boost::_bi::value<std::reference_wrapper<bool> > >; boost::_bi::bind_t<R, F, L>::result_type = void]' /usr/include/boost/thread/detail/thread.hpp:120:18: required from 'void boost::detail::thread_data<F>::run() [with F = boost::_bi::bind_t<void, boost::thread_attributes, boost::_bi::list2<boost::_bi::value<int (*)(bool&)>, boost::_bi::value<std::reference_wrapper<bool> > > >]' /usr/include/boost/thread/detail/thread.hpp:118:18: required from here /usr/include/boost/bind/bind.hpp:298:35: error: no match for call to '(boost::thread_attributes) (int (*&)(bool&), std::reference_wrapper<bool>&)' 298 | unwrapper<F>::unwrap(f, 0)(a[base_type::a1_], a[base_type::a2_]); | ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The syntax is based on this part of the manual: https://www.boost.org/doc/libs/1_79_0/doc/html/thread/thread_management.htm… Is that perhaps a feature only introduced in version 1.79 of the Boost libraries? Best wishes and thanks for any pointers, Jeanette -- * Website: http://juliencoder.de - for summer is a state of sound * Youtube: https://www.youtube.com/channel/UCMS4rfGrTwz8W7jhC1Jnv7g * Audiobombs: https://www.audiobombs.com/users/jeanette_c * GitHub: https://github.com/jeanette-c Don't care about money It doesn't give me half the thrill <3 (Britney Spears)

3 3

[Compute] Auto-determine work group size
by Stephan Menzel 12 May '22

12 May '22

Hi everyone, perhaps someone can answer a question about Boost.Compute. I have recently switched to it from using native OpenCL. Most of the things work fine except for one quirk: OpenCL allows for auto-determining the work group size when using enqueue_kernel(). As the correct work group size is still a mystery to me after using OpenCl for almost a year now I normally left this parameter to 0 to let OpenCL figure it out. With Boost.Compute and the equivalent function enqueue_nd_range_kernel() this doesn't seem to be possible. I have to use a parameter like boost::compute::extents<2>{ 8, 2 } as local_work_size. Leaving it 0 or using extents<2>{ 0, 0 } doesn't do the trick and I'm getting "Invalid work group size". This forces me to guess values until one works, which is extremely error prone and breaks all the time with images of different resolutions. Does anyone know how I can use OpenCL's auto-work-group-size feature in Boost.Compute? Cheers, Stephan

1 0

Iterating over each point within a geometry::box
by Keith Bennett 11 May '22

11 May '22

I want to iterate over every point within a geometry::model::box<point>. I want to be able to do that with iterators so that I can also use all (or most of) the standard algorithms like for_each or all_of or etc. Initially my code used several loops, one for each axis, like so for a 2d point: for (int x = box.min_corner().template get<0>(); x <= box.max_corner().template get<0>(); ++x) { for (int y = box.min_corner().template get<1>(); y <= box.max_corner().template get<1>(); ++y) { callback(point(x,y)) } } There are several places where this occurs. Some loops have the x axis first, others the y axis first -- and this has performance issues when translating the point to a container. Some loops were erroneously considering right-open intervals with less-than instead of less-than-or-equal-to comparisons. So I've had to fix bounding bugs and performance issues in multiple places that are caused by these manual loops. I've gone and unified a lot of that to use templated functions that basically duplicate some of the functionality in the standard. But that's not tractable and still doesn't use iterators so most of <algorithm> is still off-limits: namespace mynamespace { template <class box, enable_if vomit, blah blah> void for_each(const box& b, const std::function<void(const typename box::point_type&)> callback) { // the manual loops here, not repeated for brevity } } Then I've replaced most of those manual loops with calls to: mynamespace::for_each(box, [](const point& p){ // do some work here }); So I want to instead do: for (const auto& point : box) { callback(point); } Satisfying that would make a lot of places simpler and easier to read. I think it should also help to enable use of a lot of the stuff in the standard <algorithm> I understand that it might be difficult for, eg, a box containing a point with floating point types. But that's fine ... I'm only looping over integral points anyway. I'd also prefer to have the ability to control the axis order ... eg do I want x or y on the inner/outer loop? Do I want to only iterate over the y axis? I'm using C++14 and boost 1.70 at the moment. There's some friction against upgrading. But if this problem is solved in a future version -- like with C++20 ranges -- then that would be a strong point for me to convince my team to upgrade. I could go and write up some iterators myself of course. But before I do that I wondered if someone else has already solved this problem and I just haven't found the solution. Thoughts? -- Keith Bennett

1 0

Fwd: [boost] Boost MySQL Review Starts Today
by Mateusz Loskot 10 May '22

10 May '22

FYI ---------- Forwarded message --------- From: Richard Hodges via Boost <boost(a)lists.boost.org> Date: Tue, 10 May 2022 at 09:14 Subject: [boost] Boost MySQL Review Starts Today To: boost(a)lists.boost.org List <boost(a)lists.boost.org>, <boost-announce(a)lists.boost.org> Cc: Richard Hodges <hodges.r(a)gmail.com> Dear All, The Boost formal review of the MySQL library starts Today, taking place from May 10th, 2022 to May 19th, 2022 (inclusive) - We are starting one day after the announced date and extending the period by one day to compensate. The library is authored by Rubén Pérez Hidalgo (@anarthal in the CppLang slack). Documentation: https://anarthal.github.io/mysql/index.html Source: https://github.com/anarthal/mysql/ The library is built on the bedrock of Boost.Asio and provides both synchronous and asynchronous client connectors for the MySQL database system. Boost.MySQL is written from the ground up, implementing the entire protocol with no external dependencies beyond the Boost library. It is compatible with MariaDB. Connectivity options include TCP, SSL and Unix Sockets. For async interfaces, examples in the documentation demonstrate full compatibility with all Asio completion handler styles, including: Callbacks:- https://anarthal.github.io/mysql/mysql/examples/query_async_callbacks.html Futures :- https://anarthal.github.io/mysql/mysql/examples/query_async_futures.html Boost.Coroutine :- https://anarthal.github.io/mysql/mysql/examples/query_async_coroutines.html C++20 Coroutines :- https://anarthal.github.io/mysql/mysql/examples/query_async_coroutinescpp20… Rubén has also implemented the Asio protocols for deducing default completion token types :- https://anarthal.github.io/mysql/mysql/examples/default_completion_tokens.h… Reviewing a database connector in depth will require setting up an instance of a MySQL database. Fortunately most (all?) Linux distributions carry a MySQL and/or MariaDB package. MySQL community edition is available for download on all platforms here: https://dev.mysql.com/downloads/ Rubén has spent quite some time in order to bring us this library candidate. The development process has no doubt been a journey of discovery into Asio, its concepts and inner workings. I am sure he has become a fount of knowledge along the way. >From a personal perspective, I was very happy to be asked to manage this review. I hope it will be the first of many more reviews of libraries that tackle business connectivity problems without further dependencies beyond Boost, arguably one of the most trusted foundation libraries available. Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Describe as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - Will the library bring additional out-of-the-box utility to Boost? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - Will the choice of API abstraction model ease the development of software that must talk to a MySQL database? - Are there any immediate improvements that could be made after acceptance, if acceptance should happen? - 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 at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Richard Hodges - review manager of the proposed Boost.MySQL library Rubén is often available on CppLang Slack and of course by email should you require any clarification not covered by the documentation, as am I. -- Richard Hodges hodges.r(a)gmail.com tg: @rhodges office: +44 2032 898 513 mobile: +376 380 212 _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost -- Mateusz Loskot, http://mateusz.loskot.net

1 0

[Boost.Asio] [SSL] Can I set the host name before performing a handshake?
by B Aleck 04 May '22

04 May '22

In openssl you call SSL_set_tlsext_host_name to set that Can I do that in boost?

2 2

boost.org domain expired?
by Warren Weckesser 03 May '22

03 May '22

(Hit enter too soon in my last email.) FYI: Attempting to visit https://www.boost.org results in a Network Solutions page, with links for "Renew Now" and "Backorder Domain". Warren

3 3

Re: [Boost-users] boost.org domain expired?
by Kenneth Porter 03 May '22

03 May '22

Confirmed. Here's a site snapshot from yesterday in case someone needs it: https://web.archive.org/web/20220502193202/https://www.boost.org/

1 0

boost.org domain expired?
by Warren Weckesser 03 May '22

03 May '22

1 0

[Math / Distributions] How do mean, variance, etc end up in scope?
by Warren Weckesser 02 May '22

02 May '22

This is probably more of a C++ question than a Boost/Math question. I think the answer comes down to a (surprising?) Boost namespace convention. In a program like this: ``` #include <boost/math/distributions/beta.hpp> using boost::math::beta_distribution; int main() { float a = 1.5f; float b = 3.0f; beta_distribution<float> dist(a, b); auto m = mean(dist); } ``` how does the name 'mean' end up in scope in 'main()'? I would have expected (and preferred!) something like 'using boost::math::mean;' to be required. Warren

3 3

[statechart] non-virtual unconsumed_event
by Alexandre Bouchu 26 Apr '22

26 Apr '22

Hello, Looking for guidance regarding best practices using boost statechart. When it came time to have a mechanism to catch unhandled events and pass that information back to clients, my first choice has been to override unconsumed_event public function in state_machine class. Given that the static code analysis tool we run complains about the dangers of overriding a non-virtual function, I came here to get more background into maybe why this function was not made virtual in the first place. Is there for example a better implementation practice that would see this "catch all" function stay empty, as is the case with state_machine implementation, and instead use another technique to provide meaningful feedback to clients when the action or state transition requested is invalid/unsupported? I feel I can justify and waive this code analysis tool warning up the food chain, but yet wanted some feedback from this user group first. Thanks, Alexandre

1 0

constexpre limits
by Gero Peterhoff 21 Apr '22

21 Apr '22

Hello John, i switched std::numeric_limits<float128> completely to constexpr because it bothered me a lot. Especially: - quiet_NaN (removed sqrt) - has/signaling_NaN adjusted Hope that's ok. regards Gero

1 0

Unable to run example code "line_interpolate"
by Ajay Kumar G 19 Apr '22

19 Apr '22

Hello, First of all, thank you for your contributions. Indeed it was a greatly useful library with very detailed documentation. While trying to run a sample example code "line_interpolate" from following link: https://www.boost.org/doc/libs/1_79_0/libs/geometry/doc/html/geometry/refer… There is an error that appears saying " error: ‘line_interpolate’ was not declared in this scope" but i dint understand the reason. While other examples from the reference( https://www.boost.org/doc/libs/1_79_0/libs/geometry/doc/html/geometry/matri…) work fine without any issues. May I know the actual cause of this issue? Working platform: Ubuntu 18.04 Boost Version: 1.65.1.0 Regards, Ajay

2 1

[release] Boost 1.79.0
by Marshall Clow 18 Apr '22

18 Apr '22

Release 1.79.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.79.0> You can also download directly from: <https://boostorg.jfrog.io/artifactory/main/release/1.79.0/> To install this release on your system, see <http://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. -- The Boost Release Team Marshall Clow, Michael Caisse, Glen Fernandes

5 5

Boost.Intrusive: getting the next element
by Gonzalo Arana 16 Apr '22

16 Apr '22

Hi, Given an element (contained in a list), how may I get the next one, without requiring access to the list itself? I only found this way to get the next element: auto iterator = list.iterator_to(value); ++iterator; return *iterator; But it requires access to the list itself. Best regards, -- Gonzalo A. Arana

2 1

Boost.Text is looking for a (mini-)review manager
by Mateusz Loskot 15 Apr '22

15 Apr '22

Hi, A reminder from the review wizards: The Boost.Text library developed by Zach Laine is still looking for a (mini-)review manager, see details at: https://lists.boost.org/Archives/boost//2020/08/249594.php and https://www.boost.org/community/review_schedule.html Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

1 2

MySQL library scheduled for review
by Mateusz Loskot 15 Apr '22

15 Apr '22

Hi, A brief announcement from the review wizards: Following the proposal [1] and search for the review manager, formal review of the MySQL library [2] has been scheduled to take place between May 9, 2022 - May 18, 2022. Details and links available here https://www.boost.org/community/review_schedule.html We'd like to thank Richard Hodges for volunteering to act as the review manager, again! [1] https://lists.boost.org/Archives/boost/2022/03/252584.php [2] https://github.com/anarthal/mysql/ Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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[Math / Special Functions] Use more than one user_error function?
by Warren Weckesser 14 Apr '22

14 Apr '22

I am wrapping some boost special functions as NumPy "ufuncs" for the Python library SciPy, and I am setting a policy to control how errors are handled. For example, the wrapper of erf_inv (for C++ types float, double and long double) is wrapped as the function scipy.special.erfinv (i.e. the Python function is erfinv in the module scipy.special). The actual core instantiation of the function for type, say, double, in C++ that is called by the ufunc implementation is double erfinv_double(double x) { return erf_inv(x, special_policy()); } where erf_inv is the Boost function, and special_policy is created as template <class T> T user_domain_error(const char *function, const char * message, const T& val) { sf_error("erfinv", SF_ERROR_DOMAIN, NULL); return std::numeric_limits<T>::quiet_NaN(); } typedef policy< domain_error<user_error>, overflow_error<ignore_error> > special_policy; Note that the error handler is calling sf_error(), a function in the SciPy special library. The first argument is the name of the SciPy Python function. That function might generate a Python warning or set a Python exception, and the name displayed in the error message should be the name of the SciPy function, and not something like "boost::math::erf_inv[...]". This leads to the problem. The above code, with a hard-coded string "erfinv" passed to sf_error(), works for erfinv, but obviously I can't use the same implementation of user_domain_error for a wrapper of, say, tgamma_ratio. So the question is, can different policies be created that have different user-defined error handlers? Or is there a clever way to get the SciPy name into the user_domain_error() function? (I hope there is something simple--I am not a C++ guru, so I may have missed something obvious.) I am considering creating a mapping from some parsed version of the function argument of user_domain_error to the SciPy names. E.g. the function argument could be scanned for the occurrence of "erf_inv", and know that the name "erfinv" should be passed to sf_error(). A table of regex patterns with corresponding SciPy names might do the trick. But I'm wondering if there is a more elegant (and more maintainable) solution. Regards, Warren

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