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Reminder: Boost 1.84.0 release cycle starting
by Marshall Clow 04 Nov '23

04 Nov '23

The deadline for “major changes” is next Wednesday, 1-Nov. The beta release will be two weeks later. As always, the release calendar is at: https://www.boost.org/development/index.html — Marshall

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Boost test matrix
by Robert Ramey 04 Nov '23

04 Nov '23

I've merged my develop branch into the the master, waited some time, and reviewed the test results here: https://www.boost.org/development/tests/develop/developer/serialization.html . Given that we intend to release soon, I have a few questions: a) I don't see any windows compilers here. WTF? b) If I switch to "Release View" (upper left hand corner) I expect to see test runs for the master branch. I just get an error message. I can't see how we can think of doing a release with having these issues resolved. Robert Ramey

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error on inclusion of ../boost/math/special_functions/next.hpp
by Robert Ramey 03 Nov '23

03 Nov '23

In reviewing the test matrix: https://www.boost.org/development/tests/develop/developer/serialization.html I'm getting the following error message when on a couple of my tests: > Test output: teeks99-dkr-dc6-17 - serialization - test_complex_text_archive / clang-linux-6.0~c++17 > Rev 1c12b5c15fc82f0cb6d4bd931a057fc050df8a34 / Sun, 29 Oct 2023 21:39:02 +0000 > Compile [2023-10-29 23:34:25 UTC]: fail > > > "clang++-6.0" -fvisibility-inlines-hidden -Wno-c99-extensions -std=c++17 -fPIC -m64 -pthread -O0 -fno-inline -Wall -fvisibility=hidden --target=x86_64-pc-linux -ftemplate-depth-255 -DBOOST_ALL_NO_LIB=1 -DBOOST_ARCHIVE_TEST=text_archive.hpp -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_BEAST_ALLOW_DEPRECATED -DBOOST_BEAST_SEPARATE_COMPILATION -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_LIB_DIAGNOSTIC=1 -DBOOST_SERIALIZATION_DYN_LINK=1 -DBOOST_WSERIALIZATION_DYN_LINK=1 -I".." -c -o "/var/boost/run/results/boost/bin.v2/libs/serialization/test/test_complex_text_archive.test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/test_complex.o" "../libs/serialization/test/test_complex.cpp" > > In file included from ../libs/serialization/test/test_complex.cpp:19: > In file included from ../boost/math/special_functions/next.hpp:17: > In file included from ../boost/math/special_functions/trunc.hpp:21: > In file included from ../boost/math/ccmath/ldexp.hpp:15: > In file included from ../boost/math/ccmath/abs.hpp:16: > ../boost/math/ccmath/isnan.hpp:35:29: error: no template named 'is_integral_v' in namespace 'std'; did you mean 'is_integral'? > if constexpr (!std::is_integral_v<T>) > ~~~~~^~~~~~~~~~~~~ > is_integral > /usr/bin/../lib/gcc/x86_64-linux-gnu/5.4.0/../../../../include/c++/5.4.0/type_traits:289:12: note: 'is_integral' declared here > struct is_integral > ^ Looks like a minor snafu in ../boost/math/ccmath/isnan.hpp ... or not. Could someone who understands math/special functions took a look into this? On a totally separate note: I'm getting another failure on the same matrix: Test output: teeks99-dkr-dc6-17 - serialization - test_dll_simple / clang-linux-6.0~c++17 Rev 1c12b5c15fc82f0cb6d4bd931a057fc050df8a34 / Sun, 29 Oct 2023 21:39:02 +0000 Lib [2023-10-29 23:34:28 UTC]: fail See boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden where the links points to a file containing: > Test output: boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden > Rev 1c12b5c15fc82f0cb6d4bd931a057fc050df8a34 / Sun, 29 Oct 2023 21:39:02 +0000 > Compile [2023-10-29 23:34:25 UTC]: succeed > > "clang++-6.0" -fvisibility-inlines-hidden -Wno-c99-extensions -std=c++17 -fPIC -m64 -pthread -O0 -fno-inline -Wall -fvisibility=hidden --target=x86_64-pc-linux -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_BEAST_ALLOW_DEPRECATED -DBOOST_BEAST_SEPARATE_COMPILATION -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -I".." -c -o "/var/boost/run/results/boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/dll_polymorphic_derived2.o" "../libs/serialization/test/dll_polymorphic_derived2.cpp" > > In file included from ../libs/serialization/test/dll_polymorphic_derived2.cpp:13: > In file included from ../libs/serialization/test/polymorphic_derived2.cpp:15: > ../libs/serialization/test/polymorphic_base.hpp:29:13: warning: polymorphic_base imported [-W#pragma-messages] > #pragma message ("polymorphic_base imported") > ^ > In file included from ../libs/serialization/test/dll_polymorphic_derived2.cpp:13: > In file included from ../libs/serialization/test/polymorphic_derived2.cpp:16: > ../libs/serialization/test/polymorphic_derived2.hpp:32:13: warning: polymorphic_derived2 exported [-W#pragma-messages] > #pragma message ("polymorphic_derived2 exported") > ^ > 2 warnings generated. > > Link [2023-10-29 23:34:25 UTC]: succeed > > > "clang++-6.0" -o "/var/boost/run/results/boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/libdll_polymorphic_derived2.so.1.84.0" -Wl,-soname -Wl,"libdll_polymorphic_derived2.so.1.84.0" -shared -Wl,--start-group "/var/boost/run/results/boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/dll_polymorphic_derived2.o" "/var/boost/run/results/boost/bin.v2/libs/serialization/test/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/libdll_polymorphic_base.so.1.84.0" "/var/boost/run/results/boost/bin.v2/libs/serialization/build/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/libboost_serialization.so.1.84.0" "/var/boost/run/results/boost/bin.v2/libs/filesystem/build/clang-linux-6.0~c++17/debug/debug-symbols-off/threading-multi/visibility-hidden/libboost_filesystem.so.1.84.0" -Wl,-Bstatic -Wl,-Bdynamic -lrt -Wl,--end-group -fPIC -m64 -pthread -fvisibility=hidden -fvisibility-inlines-hidden --target=x86_64-pc-linux So .... This parts builds a dll/shared library which is used in the test. There doesn't seem to be anything wrong with this. Does anyone have any ideas? Robert Ramey

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Boost Security Disclosure
by Feuer, Mark 02 Nov '23

02 Nov '23

Is there a written security disclosure policy for Boost? As an example, is there a boost document that says all security vulnerabilities will be reported to NIST? If so, can someone point me to the disclosure form? I've seen in some documentation references to CVEs. Does this mean all security vulnerabilities are required to be submitted to NIST? Thanks, Mark [CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is proprietary to Medtronic and is intended for use only by the individual or entity to which it is addressed, and may contain information that is private, privileged, confidential or exempt from disclosure under applicable law. If you are not the intended recipient or it appears that this mail has been forwarded to you without proper authority, you are notified that any use or dissemination of this information in any manner is strictly prohibited. In such cases, please delete this mail from your records. To view this notice in other languages you can either select the following link or manually copy and paste the link into the address bar of a web browser: http://emaildisclaimer.medtronic.com

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[release] Master Branch is closed for major code changes
by Marshall Clow 02 Nov '23

02 Nov '23

The master branch closed for major code changes. Still open for serious problem fixes and docs changes without release manager review. The master branch will close for the 1.84.0 beta release next Wednesday As always, the calendar is available at: https://www.boost.org/development/ — The release managers

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[Release] Boost 1.84.0 closing for major changes TOMORROW
by Marshall Clow 31 Oct '23

31 Oct '23

Release closed for major code changes. Still open for serious problem fixes and docs changes without release manager review. See: https://www.boost.org/development/index.html — Marshall

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[scope] Looking for endorsements and review manager
by Andrey Semashev 31 Oct '23

31 Oct '23

Hi, This is a reminder that Boost.Scope is looking for endorsements and a review manager. Following is an excerpt from the previous announcement, describing the library. Boost.Scope is a small library implementing utilities defined in <experimental/scope> from C++ Extensions for Library Fundamentals v3 with a few extensions. Namely, the library contains: * A number of scope guards for various use cases. * A unique resource wrapper that automatically frees the resource on destruction. * Utilities for wrapping POSIX-like file descriptors in the unique resource wrapper. Compared to <experimental/scope>, some notable extensions are: * A new scope_final scope guard, which is a more lightweight alternative to scope_exit. It is accompanied with the BOOST_SCOPE_FINAL macro that allows to simplify scope guard declaration syntax. * Scope guards can be activated/deactivated multiple times. * Scope guards can be created inactive initially. * Scope guard factory functions, for compatibility with C++11. * Support for optional resource traits in unique_resource wrapper, which improves usage with resources having unallocated values. * unique_resource supports swapping. * unique_resource supports dereferencing for any resource types that support dereferencing, not only pointers. * More flexible constructors for unique_resource. The library requires C++11 at the minimum and will significantly benefit from C++17. Source: https://github.com/Lastique/scope Docs: https://lastique.github.io/scope/libs/scope/doc/html/index.html The library is tested in CI and used in production in one of my projects. Thanks.

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Use of boost::anys::unique_any in place of boost::any
by Bhuyan, Jyotideep 23 Oct '23

23 Oct '23

Hello, As per documentation, Boost::Any is getting deprecated, and it was suggested to use boost::anys::unique_any. I am using boost::any and boost::any_cast heavily in my application code. I am looking for some sample code for best practices on how we can replace boost::any and boost::any_cast with boost::anys::unique_any. I am using VS2022, boost v1.83, and building the code with C++17. Best Regards, Jyotideep Bhuyan (he/him) Please be advised that this email may contain confidential information. If you are not the intended recipient, please notify us by email by replying to the sender and delete this message. The sender disclaims that the content of this email constitutes an offer to enter into, or the acceptance of, any agreement; provided that the foregoing does not invalidate the binding effect of any digital or other electronic reproduction of a manual signature that is included in any attachment. Confidential - Company Proprietary

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[Looking for Feedback] - Fairness lib
by Federico Abrignani 22 Oct '23

22 Oct '23

Dear Boost Community, I am writing to seek feedback on a new C++ library that I have been developing (https://github.com/Sernior/fairness <https://github.com/Sernior/fairness>). This library, named "*Fairness*," is still a work in progress. Nonetheless, I believe that this is an opportune time to begin gathering feedback. *Fairness* is designed to provide fair synchronization primitives. While the standard C++ library offers various tools for managing concurrency, it does not provide mechanisms for handling fairness policies. To introduce the most fundamental component of my library, the "priority_mutex," I would like to share a simple example: /#include <thread>/ /#include <chrono>/ /#include <algorithm>/ /#include <BS_thread_pool.hpp>/ /#include <boost/fairness.hpp>/ / / /static boost::fairness::priority_mutex<4> pm;/ / / /static void busy_wait_nano(int64_t nanoseconds){/ /auto begin = std::chrono::steady_clock::now();/ /for(;std::chrono::duration_cast<std::chrono::nanoseconds>(std::chrono::steady_clock::now() - begin).count() < nanoseconds;)/ / continue;/ /}/ / / /static void thread_function_nano(int p, int preCriticalTime, int postCriticalTime, int criticalTime){/ / busy_wait_nano(preCriticalTime);/ / pm.lock(p);/ / busy_wait_nano(criticalTime);/ / pm.unlock();/ / busy_wait_nano(postCriticalTime);/ /}/ / / /int main()/ /{/ / std::array<int, 8> prios {0, 2, 2, 1, 1, 3, 3, 0};/ / std::array<int, 8> preCT {2000, 1500, 2000, 3000, 1000, 500, 500, 2000};/ / std::array<int, 8> postCT {5000, 3000, 2000, 2500, 1000, 1500, 1500, 4500};/ / int criticalTime = 1000;/ / / / BS::thread_pool pool(8);/ / / / for (int i = 0; i < 8; ++i){/ / pool.push_task(thread_function_nano, prios[i], preCT[i], postCT[i], criticalTime);/ / }/ / pool.wait_for_tasks();/ / / / return 0;/ /} / /// using BS thread pool https://github.com/bshoshany/thread-pool in this example./ / / In this example priorities are not given randomly, you can see that I gave 0 priority (the highest priority) to thread 0 which has 2000 + 1000 + 5000 and thread 7 which has 2000 + 1000 + 4500. Priority mutexes function much like a `std::array`, using a 0-indexed based system. For instance, a `priority_mutex<4>` will manage priorities ranging from 0 to 3, with 0 being the highest priority. Currently, the library comprises priority mutexes, both recursive and shared versions, along with RAII wrappers such as `unique_lock` and `shared_lock`, all of which support priorities. There are, however, some elements still missing, including priority condvars and timed versions of the mutexes. The primary motivation behind creating this library is to enhance throughput in multi-threaded pipelines. To illustrate the concept more simply, imagine a pipeline with N tasks, some of which access a protected resource. In cases of contention, there exists an optimal order of resource accesses that minimizes overall execution time, https://sernior.github.io/fairness/ <https://sernior.github.io/fairness/> the images show 2 different ways of ordering critical sections one of which is much better than the other. This library aims to empower developers, who have profiled their software, to manipulate this order with minimal performance overhead and as simply as possible. In terms of implementation, much of the development has revolved around benchmarking and testing. During this process, I've experimented with over 10 different versions of the priority mutex. Ultimately, I achieved the best results by using a priority spinlock, which is also available to library users, to provide internal atomicity to the rest of the mutexes. An essential consideration in the implementation is ensuring that the internal priority spinlock is 128 bytes away from the rest of the memory used by the mutex especially the memory used to perform the atomic::wait on. This separation helps avoid false sharing. The choice of 128 bytes aligns with processor architectures like AMD Zen 4 (the one I am testing on), as indicated in their optimization manual. I can attest that without those 128 byte separation the PM_LockUnlock benchmark was 10X worse and the PM_pipeline_benchmark_fast was worse than the std counterpart (see below for the benchmarks). Another aspect to note in the implementation is the use of 4 bytes for booleans when only a single byte is needed. This decision is related to the way atomic::wait is implemented. Most standard library implementations of atomic::wait check if the type size is supported by the current platform's wait syscall. For instance, Windows can wait on 1 byte, while Linuxkernel based systems can only wait on 4 bytes. These are some benchmark results: 6.4.0-kali3-amd64 AMD Ryzen 5 7600X 6-Core Processor Now the LockUnlock benchmarks were the most difficult to optimize. Those are 8 threads simply doing: m.lock(); m.unlock(); The pipeline benchmarks (with different lenght) are actual pipelines where each thread has different times before/during/after the critical section and I try to set the priorities accordingly to finish as soon as possible. You can see there is also a mutex called slim_priority_mutex, that is a priority_mutex implementation that can support up to 7 (15 if boost atomic is found and your hardware supports the DWCAS) priorities. Those are light weight versions that only take 128 bits up to 7 priorities and past that, up to 15, 256 bits. I am also testing with a custom wait implementations (https://github.com/Sernior/fairness/blob/main/include/boost/fairness/detail… <https://github.com/Sernior/fairness/blob/main/include/boost/fairness/detail…>) which can be tested by defining BOOST_FAIRNESS_USE_EXPERIMENTAL_WAIT_NOTIFY. At some point I wish to make this wait the default version the lib uses instead of the std one since users of my lib could configure this version using my configs macros (number of fast spins - relaxed spins - yield spins before the wait syscall). As I said in the beginning other than to present my lib, this email has the purpose of obtaining feedback. I would like to see if there is anyone (other than me) interested in what I am doing and, if so, consider that I am still far from finished and I would love suggestions. Thank you all for your attention. Best regards, Federico Abrignani.

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[boost.async] new name
by Klemens Morgenstern 13 Oct '23

13 Oct '23

Given the renaming requirement, I'd like to query the list if there are any objections to any of the following names: async.core await co_async / cosync co20 / cor20 Thanks, Klemens

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