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boost.numpy functions are throwing unresolved extern symbol link errors
by Max Fetz 20 Jan '21

20 Jan '21

Hello Boost-Community I have asked the following question everywhere but nowhere has it been answered. I have now been advised to ask here. I really hope there is someone on this mail list who can help me. Unfortunately I don't have much time left and would be very grateful for an answer. With kind regards Max My Question: I'm using normal Boost.NumPy functions in C++ like ndarray::get_data(), and I get a "reference to unresolved external symbol" error. The .lib's are linked and I have no approach on how to solve the error. I am using Boost 1.74. Here is a Code example: #include<boost/python/numpy.hpp> using namespace boost; void func(python::object _obj) { python::numpy::ndarray my_ndarray = python::extract<boost::python::numpy::ndarray>(_obj.attr("Member_01")); char* data = my_ndarray.get_data(); } BOOST_PYTHON_MODULE(ogwa_acc) { python::def("func", func); } Thats the one of the unresolved symbols: ""__declspec(dllimport) public: char * __cdecl boost::python::numpy::ndarray::get_data(void)const " (_imp?get_data@ndarray@numpy@python@boost@@QEBAPEADXZ)" I am using the normal Visual Studio linker and this is my linker config: /OUT:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pyd" /MANIFEST /NXCOMPAT /PDB:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pdb" /DYNAMICBASE "boost_numpy38-vc142-mt-gd-x64-1_74.lib" "boost_numpy38-vc142-mt-x64-1_74.lib" "boost_python38-vc142-mt-gd-x64-1_74.lib" "boost_python38-vc142-mt-x64- 1_74.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /IMPLIB:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.lib" /DEBUG /DLL /MACHINE:X64 /INCREMENTAL /PGD:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pgd" /SUBSYSTEM:CONSOLE /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"x64\Debug\ogwa_acc.pyd.intermediate.manifest" /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"C:\Program Files\Python38\libs" /LIBPATH:"D:\OthelloGame_withAI\Third-Party\boost_1_74_0\finished_libs" /TLBID:1 D:\OthelloGame_withAI\Third-Party\boost_1_74_0\finished_libs is the location of: boost_numpy38-vc142-mt-gd-x64-1_74.lib; boost_python38-vc142-mt-gd-x64- 1_74.lib; boost_numpy38-vc142-mt-x64-1_74.lib; boost_python38-vc142-mt-x64-1_74.lib

4 4

[build] b2 headers broken?
by John Maddock 16 Jan '21

16 Jan '21

Currently all CI seems to be failing during b2 headers, but with no obvious error message, see for example: https://drone.cpp.al/boostorg/multiprecision/23/1/2 Only possible thing I can see is: project-config.jam:10: syntax error at keyword in Anyone any ideas? Many thanks, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

3 5

Feedback desired for neural networks library
by Sergei Marchenko 11 Jan '21

11 Jan '21

Hi everyone, I have a template-based library with several common types of layers which can be assembled into various neural networks: https://github.com/svm-git/NeuralNet, and I would love to get community feedback on the overall design, any issues or missing features, and how interesting a library like that would be in general. I've been watching the trends and research reports in the AI/ML space, and I feel that the recent announcements of the successful models for image classification, computer vision or natural language processing, push the focus towards very complex and computationally intensive networks. However, I think that the idea behind multi-layer networks is very powerful, and is applicable in many domains, where even a small and lightweight model can be used successfully. I also think that if developers have an access to a library of building blocks that allows them to train and run NN anywhere a C++ code can run, it may encourage a lot of good applications. In the current state, the library is fairly small and should be easy to review. It was built with two main goals in mind: * Provide a collection of building blocks that share a common interface which allows plug'n'play construction of more complex NNs. * Compile-time verification of the internal consistency of the network. I.e. if a layer's output size does not match the next layer's input, it is caught at the very early stage. Once it seems like there is some consensus on the core design and usefulness of such library, I am willing to do the work necessary to make the library consistent with Boost requirements for naming convention, folder structure, unit tests etc. The library relies on the C++ 11 language features and has a dependency on just a few STL components, so I think it should be straightforward to merge into Boost. Best regards, Sergei Marchenko.

6 15

Can boost ASIO SSL run one way SSL?
by Jupiter 11 Jan '21

11 Jan '21

Hi, There is an example for running boost::asio::ssl for boost::asio::ip::tcp connection, it uses 2 way SSL which client uses the key and certificates to have two way SSL handshake. My boss asked me if it can be used for one way SSL similar to HTTPS, I don't think so, but I could be wrong. Appreciate your advice. Thank you. Kind regards, jupiter

2 3

Problem building Ceph 14.2.15 with libboost 1.74.0
by Thomas Goirand 07 Jan '21

07 Jan '21

Hi, I'm the Debian package maintainer for Ceph. Ceph currently fails to build with latest libbost. Here's the build log: /root/ceph/src/common/async/completion.h:194:29: error: 'boost::asio::executor_work_guard<boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context&>, boost::asio::execution::detail::blocking::never_t<0>, boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0> > >, void>::executor_type' {aka 'class boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context&>, boost::asio::execution::detail::blocking::never_t<0>, boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0> > >'} has no member named 'defer'; did you mean 'prefer'? 194 | w.second.get_executor().defer(std::move(f), alloc2); and 3 more like this. The code doing this is in src/common/async/completion.h: void destroy_defer(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().defer(std::move(f), alloc2); } void destroy_dispatch(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().dispatch(std::move(f), alloc2); } void destroy_post(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().post(std::move(f), alloc2); } Has the boost API changed? If so, how to fix the above code? Thanks a lot to anyone helping me fixing this, Cheers, Thomas Goirand (zigo)

2 2

[uBlas] [Tensor] multiprecision and FFT?
by Janek Kozicki 07 Jan '21

07 Jan '21

Cem Bassoy via Boost said: (by the date of Wed, 6 Jan 2021 10:32:15 +0100) > Please consider to use and contribute to *Boost.uBlas* Hi, Does it work with boost::multiprecision types? In particular I am interested in types listed here: http://yade-dem.org/doc/HighPrecisionReal.html Does it support FFT ? In particular I am interested in replacing my very crude NDimTable class with your code: https://gitlab.com/cosurgi/trunk/-/blob/addQuantumMechanics_FixEnum_FixReba… I am about to start refactoring this part of the code, when I noticed your post. best regards Janek -- Janek Kozicki, PhD. DSc. Arch. Assoc. Prof. Gdańsk University of Technology Faculty of Applied Physics and Mathematics Department of Theoretical Physics and Quantum Information -- http://yade-dem.org/ http://pg.edu.pl/jkozicki (click English flag on top right)

2 3

C++11 on up Boost libraries
by Edward Diener 04 Jan '21

04 Jan '21

In my effort to set the meta information of 'cxxstd' for the appropriate C++11 on up libraries, my PRs for these libraries have been kindly merged to 'develop' by the library maintainers: beast callable_traits context convert coroutine2 fiber geometry gil hana histogram hof json leaf mp11 nowide outcome pfr process safe_numerics static_string stl_interfaces variant2 yap If anyone knows of any other current library which is a C++11 on up library, please tell me. My testing showed that all other Boost libraries will work in C++03 mode, but maybe I missed some other library which is a C++11 on up library. Needless to say other libraries have noted their attention to move from C++03 to C++11 in the near future. If any library does change the C++ mode necessary to use that library, I hope the maintainer(s) of that library will update the 'cxxstd' meta information appropriately. If we can get the website to work properly using the 'cxxstd' meta information, end-users should be able to know immediately whether a Boost library is usable depending on the C++ standard mode their are using.

10 20

Develop is broken on MSVC (b2 issue?)
by Antony Polukhin 04 Jan '21

04 Jan '21

I see a bunch of CI failures https://apolukhin.github.io/en/developer.html for different versions of MSVC. There are some complains on 'cl': compile-c-c++ ..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj 'cl' is not recognized as an internal or external command, operable program or batch file. call "..\..\..\bin.v2\standalone\msvc\msvc-9.0\msvc-setup.bat" amd64 >nul cl /Zm800 -nologo "track_13621.cpp" -Fo"..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj" -TP -DBOOST_TRAVISCI_BUILD /wd4675 /EHs /GR /O2 /Ob2 /W3 /MD /Zc:forScope /Zc:wchar_t /favor:blend -c -DBOOST_ALL_NO_LIB=1 -DNDEBUG "-I..\..\.." ...failed compile-c-c++ ..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj... Is that a known issue?

3 3

Regression Test Failures On develop branch
by Tom Kent 02 Jan '21

02 Jan '21

I just noticed that the develop branch has started to fail to run the develop branch, crashing early on in the run. The failures started sometime between 2020-12-31_03:52:29 PST (2020-12-31_11:52:29 UTC) (last good run) and 2020-12-31_06:57:54 PST (2020-12-31_14:57:54 UTC) (first failing run). These are still continuing with the latest develop branch. It looks like there were only a couple commits to boostorg/boost/develop in this window, and update to multiprecision (only changing meta/libraries.json) and a few changes to build. The error looks fairly non-descript... D:\teeks99-09\run\boost_root\status>"D:\teeks99-09\run\boost_bb\src\engine\bjam.exe" "-sBOOST_BUILD_PATH=D:\teeks99-09\run;D:\teeks99-09\run\boost_bb\src" "-sBOOST_ROOT=D:\teeks99-09\run\boost_root" "--boost=D:\teeks99-09\run\boost_root" "--boost-root=D:\teeks99-09\run\boost_root" "--boost-build=D:\teeks99-09\run\boost_bb\src" "--debug-configuration" -l300 toolset=msvc-11.0 -d2 preserve-test-targets=off --dump-tests -j8 address-model=64 --remove-test-targets --abbreviate-paths debug-symbols=off -m64 "--build-dir=D:\teeks99-09\run\results" 1>>"D:\teeks99-09\run\results\bjam.log" 2>&1 # Running Boost.Build tests Traceback (most recent call last): File "run.py", line 71, in <module> runner(root) File "D:\teeks99-09\run\boost_regression_src\regression.py", line 286, in __init__ self.main() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 623, in main getattr(self,action_m)() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 588, in command_regression self.command_test() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 367, in command_test self.command_test_boost_build() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 409, in command_test_boost_build "boost/bin.v2/libs/any/test/any_test.test")); WindowsError: [Error 3] The system cannot find the path specified: 'D:\\teeks99-09\\run\\results\\boost/bin.v2/libs/any/test/any_test.test\\*.*' At the end of my result-bjam.log file, I get this, but not sure if it is related. Performing configuration checks - default architecture : x86 - default address-model : 64-bit - symlinks supported : no - junctions supported : yes - hardlinks supported : yes - BOOST_COMP_GNUC >= 4.3.0 : no - has_icu builds : no - compiler supports SSE2 : yes - compiler supports SSE4.1 : yes - has synchronization.lib : yes - cxx11_constexpr : no - cxx11_decltype : yes - cxx11_hdr_tuple : no - cxx11_template_aliases : no - cxx11_variadic_templates : no - OpenCL : no - C++11 mutex : yes - has BCrypt API : yes - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : yes - cxx11_defaulted_functions : no - cxx11_final : yes - cxx11_hdr_mutex : yes - cxx11_lambdas : yes - cxx11_noexcept : no - cxx11_nullptr : yes - cxx11_rvalue_references : yes - cxx11_thread_local : no - cxx11_trailing_result_types : no warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - cxx14_constexpr : no - cxx14_decltype_auto : no - cxx14_generic_lambdas : no - cxx14_return_type_deduction : no - cxx11_user_defined_literals : no - cxx11_alignas : no - iconv (libc) : no - iconv (separate) : no - icu : no - icu (lib64) : no - native atomic int32 supported : yes - has message compiler : yes - native syslog supported : no - pthread supports robust mutexes : no - compiler supports SSSE3 : yes - compiler supports AVX2 : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - !BOOST_COMP_GNUC : yes - BOOST_COMP_GNUC >= 6.0 : no - !BOOST_COMP_CLANG : yes - BOOST_COMP_CLANG >= 4.0 : no - cxx14_variable_templates : no - BOOST_COMP_GNUC >= 4.7.4 : no error: No best alternative for ../libs/accumulators/test/accumulators_test_valarray next alternative: required properties: <link>static <target-os>linux <toolset>clang not matched next alternative: required properties: <link>static <target-os>darwin not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_test_tail_variate_means next alternative: required properties: <link>static <toolset-msvc:version>14.0 <toolset>msvc not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_tests_pot_quantile_and_weighted_tail next alternative: required properties: <link>static <target-os>linux <toolset-gcc:version>4.4.7 <toolset>gcc not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_test_weighted_tail_variate_means next alternative: required properties: <link>static <target-os>linux <toolset-gcc:version>4.4.7 <toolset>gcc not matched next alternative: required properties: <link>static <toolset-msvc:version>14.0 <toolset>msvc not matched next alternative: required properties: <link>static not matched - cxx11_constexpr : no - cxx11_decltype : yes - cxx11_hdr_tuple : no - cxx11_template_aliases : no - cxx11_variadic_templates : no - OpenCL : no - has_atomic_lib builds : no - has_pthread_lib builds : no - has_rt_lib builds : no - Clang implicit fallthrough : no - int128 : no - cpp_lib_complex_udls : no - cpp_range_based_for_17 : no - cxx11_hdr_thread : yes - cxx11_variadic_macros : yes - cxx11_hdr_unordered_set : yes - mixed_cxxstd builds : yes - mixed_cxxstd builds : yes - cxx11_hdr_array : yes - cxx11_defaulted_functions : no - cxx11_trailing_result_types : no notice: [libjpeg] Using pre-installed library notice: [libjpeg] Condition notice: [zlib] zlib is already configured notice: [libpng] Using pre-installed library notice: [libpng] Condition notice: [libtiff] Using pre-installed library notice: [libtiff] Condition - cxx14_constexpr : no - cxx14_decltype_auto : no - cxx14_generic_lambdas : no - cxx14_return_type_deduction : no - cxx11_user_defined_literals : no - Checking for gmpxx.h : no - zlib : no - bzip2 : no - lzma : no - zstd : no - lzma : no (cached) - has_lzma_cputhreads builds : no - cxx11_alignas : no - message-compiler : yes - message-compiler : yes - cxx11_unified_initialization_syntax : no - cxx11_smart_ptr : yes - GCC libquadmath and __float128 support : no - cxx11_hdr_initializer_list : no - sfinae_expr : no - cxx11_inline_namespaces : no - cxx11_range_based_for : yes - libfftw3 : no - __float128 : no - has_ntl_rr builds : no - has_mpfr_class builds : no - has_mpreal builds : no - has_e_float builds : no - gcc visibility : no - long double support : yes - cxx17_if_constexpr : no - cxx17_std_apply : no - has_eigen builds : no - Intel _Quad datatype support : no - has_mpfr builds : no - cxx11_hdr_atomic : no - cxx11_hdr_future : yes - cxx11_hdr_chrono : yes - cxx11_hdr_random : yes - cxx11_allocator : no - 128-bit floatmax_t : no - cxx11_numeric_limits : yes - cxx11_explicit_conversion_operators : no - cxx11_function_template_default_args : no - BOOST_MULTI_INDEX_KEY_SUPPORTED defined : no - has_gmp builds : no - has_tommath builds : no - has_mpfi builds : no - has_float128 builds : no - has_intel_quad builds : no - has_mpc builds : no - has_is_constant_evaluated builds : no - has_constexpr_limits builds : no - has_gmp builds : no - has_mpfr builds : no - has_big_obj builds : no - has_f2c builds : no - cxx11_noexcept : no - cxx11_rvalue_references : yes - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - cxx11_hdr_chrono : yes - !BOOST_COMP_GNUC : yes - BOOST_COMP_GNUC >= 6.0 : no - !BOOST_COMP_CLANG : yes - BOOST_COMP_CLANG >= 4.0 : no - cxx14_variable_templates : no - cxx17_structured_bindings : no - cxx17_structured_bindings : no - compiler_supports_loophole builds : yes - compiler_supports_loophole builds : yes - cxx11_hdr_unordered_map : yes WARNING: Unable to construct ../libs/predef/test/info_as_objcpp of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objcpp.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } WARNING: Unable to construct ../libs/predef/test/info_as_objc of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objc.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } - BOOST_OS_MACOS : no - BOOST_COMP_CLANG > 0.0.0 : no - BOOST_OS_LINUX == 0 : yes WARNING: Unable to construct ../libs/predef/test/info_as_objcpp of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objcpp.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } WARNING: Unable to construct ../libs/predef/test/info_as_objc of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objc.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } - zlib : no (cached) - bzip2 : no (cached) - lzma : no (cached) - zstd : no (cached) - zlib : no - bzip2 : no - lzma : no - zstd : no - auto_ptr : yes - cxx11_lambdas : yes - std_wstreambuf : yes - cxx11_hdr_forward_list : yes Happy new year! Tom

2 2

Re: [boost] Boost website changes and .'cxxstd`
by Donovan Dikaio 30 Dec '20

30 Dec '20

Hi Edward, you're right. The beta website link is https://beta.boost.org/ FYI, there is a file 'libraries.txt' in the source codes which contains all the libraries info. It looks like that it can be generated by a site tool. To my codes review, there exist multiple records for a library for various versions in the above text file. And the codes check and compare a library record’s version info with the current version, and pick one matching a condition. There is no record with 'cxxstd' field at the text file for beta website but for main site. Unfortunately, there is no one to match version comparison condition for main site as well at the moment. The updates codes of beta website will only show 'C++ standard minimum level' with 'cxxstd' value only if a 'cxxstd' value exists.

2 1

Potential order statistic tree?
by Soronel Haetir 29 Dec '20

29 Dec '20

Boost developers, Would there be interest in adding an order statistic tree to the boost library? That is, a tree that instead of being sorted simply keeps nodes in whatever order is specified, along with a (potentially multi-index) per-node value and a total of per-node values of each node and its left-descent tree. I currently have two such types, a very capable intrusive version (not based on boost::intrusive though using some of the same ideas) and a less capable non-intrusive form that uses the mechanics of the intrusive form as an implementation detail. The reason for not being based on Boost.Intrusive is that the tree algorithms that Boost.Intrusive provides are all for search trees and this very definitely is not, plus the need to alter node weights during insert, delete and rotations and the Boost.Intrusive algorithm providers not having a good place to add that behavior. I have personally found this type very useful while implementing a rope container and also while implementing tracking for various parts of a text editor (that is, paragraph, line and run positions) (in terms of characters, graphemes and screen height). Perhaps the major drawback to what I have is that I have not been careful to isolate c++-version dependent code. Although I know it does compile with the latest msvc 2019 as well as the clang 10.0 that MS ships. I am simply not sure whether such a type has a broad enough appeal to make the work of adding it to boost worthwhile. -- Soronel Haetir soronel.haetir(a)gmail.com

4 3

Boost website changes and .'cxxstd'
by Edward Diener 24 Dec '20

24 Dec '20

Even though I have worked a little with PHP in the past I do not have the talent to make the change to the website which would incorporate the addition of the meta information json field 'cxxstd' to the Boost documentation web page for each library. The idea is that if 'cxxstd' is set to a value the documentation for that library would also show: C++ standard minimum level: C++nn where nn would be 11, 14, 17, or 20 depending on the value of 'cxxstd'. Alternatively if there is no 'cxxstd' entry for a library or if the value of 'cxxstd' is '03', we could either specify 'nn' as '03' or leave off the line stating the 'C++ standard minimum level completely. On the face of it this should be doable in the website code but evidently Daniel James is the only one who really understands how this works in the code and he is no longer active in Boost. So if someone else who understands the website code and PHP could do this it would be appreciated, since I think it will be valuable telling end-users whether a Boost library is usable at the C++ compiler level they are using.

3 3

(no subject)
by Harsh 21 Dec '20

21 Dec '20

Respected Sir/Madam Myself Harsh Agarwal a highly interested candidate to work on with ublas as a open source contributor but at starting need some guidance-: 1-:How can i start on with it. 2-: As if i want to participate in Gsoc 2021 till when will i get competency test. 3-: can i know about the basic project idea that will be for gsoc 2021 thanking you Harsh Agarwal 21/12/2020

2 1

regarding boost gsoc competency test 2021
by Mohd Huzaifa 20 Dec '20

20 Dec '20

hii sir/madam I want to ask about the boost competency test for gsoc 2021. When it will be available. And can I get the list of past competency tests.

2 1

Tagging the minimum C++ standard level for Boost libs
by Edward Diener 19 Dec '20

19 Dec '20

I had previously proposed that we tag the minimum C++ standard level for Boost libs by adding information to the json meta information in libraries.json for each library. I would like to revisit that proposal, which involved more elaborate suggestions, with this simpler overall proposal: for each Boost C++ library whose minimum C++ standard level is C++11 or above we add a json field called 'cxxstd' whose value corresponds to one of the same values as currently exists in Boost.Build for the 'cxxstd' feature, ie. 11,14,17,20, to the libraries.json file for that library. This json value can then be used in Boost documentation of each library to specify the minimum C++ standard level needed by an end-user in order to use that library. Obviously we can also add "cxxstd": "03" for the many Boost libraries which can still be used at the C++98/C++03 compilation level also, even though I would argue that not having a "cxxstd" json field should mean C++98/C++03 by default. I would be willing to create the necessary PRs for each library, as I have a pretty good internal list of this information. The gist of this proposal is to make it much easier for end-users wishing to use a Boost library to immediately know whether the library they wish to use is usable at the C++ standard compilation level they are using for compilation, without having to spend time searching for such information, which is often not readily available, in the documentation of the library they are considering. I can go ahead and start doing this now, but of course I am willing to listen to what others think about this. But let's not let another round of inertia stop doing at all what should be a simple means of telling end-user's whether a Boost library is at least minimally usable by them in their C++ projects.

5 13

Re: [boost] [release] Boost 1.75.0 Release Candidate 1
by Glen Fernandes 17 Dec '20

17 Dec '20

On 2020-12-13 03:34:00 Glen Fernandes wrote: > > On Sat, Dec 12, 2020 at 8:16 PM Edward Diener wrote: >> The final issue was that the index.html for the release showed 1.74 >> rather than 1.75. This seems to be generated from some sort of template >> where '{{version}}' is supposed to be plugged in by the correct version, >> but evidently did not work properly. Maybe someone who knows how this is >> supposed to work, but evidently did not, can look at it. > > Sounds like generate.php?page=index.html&version=<version> was invoked > with the wrong <version> . I'll take a look and see what I can find. Fixed: https://github.com/boostorg/release-tools/commit/b08dbc34451e9f5b09ec44cab5… Glen

1 0

Boost Pub/Sub message service model Implementation
by Rakshita Parihar 15 Dec '20

15 Dec '20

Hello, Currently, I am working on an IoT project where I need to send data from client to server. To transfer data, I need to setup a Pub/Sub message service model. Presently, I am using MQTT Paho C libraries to transmit data to server over TCP IP protocol but I want to switch to boost C++ library for the publish/subscribe model. I am a newbie to this library and have some queries: *1) Is there any boost C++ library for pub/sub model? If yes, please give me the details or link for the tutorial.* *2) If no library is present, please tell me how to implement a message pub/sub <https://en.wikipedia.org/wiki/Publish%E2%80%93subscribe_pattern> service to communicate using boost C++ library?* Please, help me to solve these issues. Thanks & Regards, Rakshita Parihar

5 5

[release] Boost 1.75.0 Release Candidate 1
by Marshall Clow 13 Dec '20

13 Dec '20

[release] Boost 1.75.0 Release Candidate 1 The first release candidates for the 1.75.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.75.0/source/> The SHA256 checksums are as follows: caf36d7c13b3d8ce62282a64a695113945a13b0f1796a45160726d04295f95ed boost_1_75_0_rc1.zip aeb26f80e80945e82ee93e5939baebdca47b9dee80a07d3144be1e1a6a66dd6a boost_1_75_0_rc1.tar.gz 953db31e016db7bb207f11432bef7df100516eeb746843fa0486a222e3fd49cb boost_1_75_0_rc1.tar.bz2 3a8b314871646e7404886736273c053278ba71b11347f72d4751411d65d6d1a5 boost_1_75_0_rc1.7z As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

6 11

bootstrap was broken since 1.74
by Neo Anderson 12 Dec '20

12 Dec '20

Hi List, I am a casual user of boost library. I usually build boost for use to build CodeBlocks IDE on Windows platform. But since version 1.74, I found that bootstrap.bat was broken. So I skipped 1.74 and stuck to the old version 1.73. Today I am happy to see that 1.75 was out and I thought this problem would have been fixed since it’s a small problem. But I am wrong. I think line 15 lacks command line parameter: call .\build.bat %1. After adding that %1, I successfully built b2 with bootstrap.cmd gcc. But when I run .\b2, I get very confusing error messages (which are the same ones in 1.74): C:\Build\src\boost_1_75_0>.\b2 Performing configuration checks - default address-model : 32-bit - default architecture : x86 Building the Boost C++ Libraries. - compiler supports SSE2 : yes - compiler supports SSE4.1 : yes - has synchronization.lib : yes - C++11 mutex : yes - has BCrypt API : yes - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : yes - cxx11_constexpr : yes - cxx11_defaulted_functions : yes - cxx11_final : yes - cxx11_hdr_mutex : yes - cxx11_hdr_tuple : yes - cxx11_lambdas : yes - cxx11_noexcept : yes - cxx11_nullptr : yes - cxx11_rvalue_references : yes - cxx11_template_aliases : yes - cxx11_thread_local : no - cxx11_variadic_templates : yes - has_icu builds : no warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - zlib : yes - bzip2 : no - lzma : no - zstd : yes - lzma : no - has_lzma_cputhreads builds : no - cxx11_alignas : yes - cxx11_decltype : yes - iconv (libc) : no - iconv (separate) : yes - icu : no - icu (lib64) : no - native atomic int32 supported : yes - has message compiler : no - native syslog supported : no - pthread supports robust mutexes : no - compiler supports SSSE3 : yes - compiler supports AVX2 : yes - gcc visibility : yes - long double support : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - Has Large File Support : yes warning: No python installation configured and autoconfiguration note: failed. See http://www.boost.org/libs/python/doc/building.html note: for configuration instructions or pass --without-python to note: suppress this message and silently skip all Boost.Python targets - libbacktrace builds : no - addr2line builds : no - WinDbg builds : yes - WinDbgCached builds : no - BOOST_COMP_GNUC >= 4.3.0 : yes - zlib : yes (cached) - bzip2 : no (cached) - lzma : no (cached) - zstd : yes (cached) - compiler supports SSE2 : no - compiler supports SSE4.1 : no - has synchronization.lib : no - C++11 mutex : no - has BCrypt API : no - is Windows CE : no - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : no - cxx11_constexpr : no - cxx11_defaulted_functions : no - cxx11_final : no - cxx11_hdr_mutex : no - cxx11_hdr_tuple : no - cxx11_lambdas : no - cxx11_noexcept : no - cxx11_nullptr : no - cxx11_rvalue_references : no - cxx11_template_aliases : no - cxx11_thread_local : no - cxx11_variadic_templates : no - native atomic int32 supported : no - has message compiler : no - native syslog supported : no - pthread supports robust mutexes : no - has_icu builds : no - compiler supports SSSE3 : no - compiler supports AVX2 : no C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:609: in start-building from module targe ts error: Recursion in main target references error: the following target are being built currently: error: ./forward ./stage ./stage-proper libs/filesystem/build/stage libs/filesystem/build/stage-depe ndencies libs/log/build/stage libs/log/build/stage-dependencies libs/filesystem/build/stage C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:776: in class(a)main-target.generate from module object(main-target)@7282 C:/Build/src/boost_1_75_0/tools/boost_install\boost-install.jam:1176: in generate-dependencies from module boost-install C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:107: in modules.call-in from module boo st-install C:/Build/src/boost_1_75_0/tools/build/src/util\indirect.jam:105: in indirect.call from module indire ct C:/Build/src/boost_1_75_0/tools/build/src/tools\generate.jam:59: in construct from module object(gen erated-target-class)@2809 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1364: in class(a)basic-target.generate fro m module object(generated-target-class)@2809 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@11221 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@11221 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@2810 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@2810 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@11222 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@11222 C:/Build/src/boost_1_75_0/tools/boost_install\boost-install.jam:1176: in generate-dependencies from module boost-install C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:107: in modules.call-in from module boo st-install C:/Build/src/boost_1_75_0/tools/build/src/util\indirect.jam:105: in indirect.call from module indire ct C:/Build/src/boost_1_75_0/tools/build/src/tools\generate.jam:59: in construct from module object(gen erated-target-class)@1817 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1364: in class(a)basic-target.generate fro m module object(generated-target-class)@1817 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@7281 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@7281 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@1818 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@1818 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@7282 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@7282 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@184 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@184 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5196 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5196 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(top-level-target)@190 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in alias-target-class.generate fro m module object(top-level-target)@190 C:/Build/src/boost_1_75_0\boostcpp.jam:403: in build-multiple from module object(top-level-target)@1 90 C:/Build/src/boost_1_75_0\boostcpp.jam:393: in class(a)top-level-target.generate from module object(to p-level-target)@190 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5198 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5198 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(top-level-target)@191 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in alias-target-class.generate fro m module object(top-level-target)@191 C:/Build/src/boost_1_75_0\boostcpp.jam:403: in build-multiple from module object(top-level-target)@1 91 C:/Build/src/boost_1_75_0\boostcpp.jam:393: in class(a)top-level-target.generate from module object(to p-level-target)@191 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5199 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5199 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:273: in class(a)project-target.generate fr om module object(project-target)@134 C:/Build/src/boost_1_75_0/tools/build/src\build-system.jam:797: in load from module build-system C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:295: in import from module modules C:/Build/src/boost_1_75_0/tools/build/src/kernel/bootstrap.jam:139: in boost-build from module C:/Build/src/boost_1_75_0/boost-build.jam:17: in module scope from module

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[release] Boost 1.75.0
by Marshall Clow 11 Dec '20

11 Dec '20

Release 1.54.0 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 1 new library and numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.75.0> You can also download directly from: <https://dl.bintray.com/boostorg/release/1.75.0/> 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. Thanks, -- The Boost Release Team Marshall Clow, Glen Fernandes, Michael Caisse

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[release] 1.76.0 open for merging
by Marshall Clow 11 Dec '20

11 Dec '20

The master branch is open for merging all stable changes from develop, including bug fixes and major upgrades to existing libraries. Breaking changes should be coordinated via the mailing list with the developers of the other libraries affected. New libraries may be added, but require permission of a release manager. In other words, merging does not require permission from a release manager, except for new libraries. Boost Calendar with the release schedule: http://www.boost.org/development/index.html <http://www.boost.org/development/index.html> Release schedule explanation: https://github.com/boostorg/wiki/wiki/Releases%3A-Schedule <https://github.com/boostorg/wiki/wiki/Releases%3A-Schedule> Release practices for developers: http://svn.boost.org/trac/boost/wiki/ImprovingPractices <http://svn.boost.org/trac/boost/wiki/ImprovingPractices> -- The Boost Release Team

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The new Boost 17.0.0
by Antony Polukhin 10 Dec '20

10 Dec '20

Hi, == The problem. TL;DR: we are having huge troubles with usability and popularity! Quite a lot of companies forbid using Boost because: * it provides vocabulary types, that should be the same across the whole project (like shared_ptr, filesystem::path or optional). Otherwise it's hard to combine different APIs * it is huge, in consists of legacy on more than a half, with a lot of dependencies between libraries. This is extremely painful for big companies, because there's no efficient distributed build system. Each company invents it's own and/or tries to minimize headers by all means. New companies (startups) also avoid Boost: * "We are using C++17, we do not want legacy libraries with C++98 support" * Junior developers are confused by multiple vocabulary types. "Should we use boost::optional or std::optional?" * hard to upgrade, because symbols are not versioned ISO C++ WG21 community not willing to push prototypes into Boost. "We aim to establish "existing practice" and provide reference implementations so that Boost libraries are suitable for eventual standardization." - that's not really true any more. == The Solution TL;DR: we need a C++17 fork of Boost with close to 0 dependencies between libraries and namespace versioning. С++17 provides many vocabulary types, feature test macro and a bunch of features for variadic templates. All of that allows us to drop a lot of weight and fix majority of popularity and usability problems. Rule of a thumb should be: "If the C++17 provides that functionality - use the standard version". That approach would allow to loose a lot of weight, do not mess with vocabulary types and significantly reduce dependencies https://pdimov.github.io/boostdep-report/master/module-levels.html By levels: config 0 -> we probably would not need it any more assert 1 -> 0 core 2 -> 1 (or 0 if we merge it with asser) smart_ptr 4 -> 2 exception 5 -> 2 stacktrace 5 -> 2 intrusive 5 -> 2 outcome 6 -> 3 container 6 -> 3 gil 11 -> 2? context 16 -> 2? dll 17 -> 1 asio 18 -> 3? beast 19 -> 4? == The Path TL;DR: we should start the Boost17 now and ship it as we are ready. Old Boost should be still available. The new approach requires quite a lot of effort and not all the maintainers have enough time to do the migration. We should keep releasing the existing Boost, while migrating the libraries to the Boost17. The migration is not as hard as it seems. It took 2 or 3 days to make Boost.DLL work with either boost or std filesystem. It could be done in less than a day, if I do not have to support the Boost filesystem. == Action points 0) Discuss 1) Bury the idea, wait for a few years, goto 0); or make a boost17 repo with the same layout as the existing one, but without submodules 2) start the migration -- Best regards, Antony Polukhin

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[release] Master branch now closed for 1.75.0 release
by Marshall Clow 09 Dec '20

09 Dec '20

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qvm: return type for mixed scalar type vector operations
by Kai Szuttor 09 Dec '20

09 Dec '20

Hey all, concerning vector operations in boost qvm, is it possible to somehow specify the return type of a binary operator with mixed scalar input data, e.g. operator+(vec<double, 3>, vec<int, 3>) ? Could not find the customisation point to do this depending on the involved operation. Thanks in advance, Kai

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Re: [boost] Boost Digest, Vol 6513, Issue 3
by Brian Wood 07 Dec '20

07 Dec '20

Peter Dimov writes: > Marshall Clow wrote: > > > I must concur with Ville here; I have had several people tell me they > won?t > > use Boost because ?it changes with every release?. > > Boost does change with every release, and I still keep using 1.38 in > several > projects of mine, but these changes are not limited to ABI at all. > Everything changes, you have to retest the whole lot, for correctness as > well as performance. > > And in general, expecting ABI stability from a collection of predominantly > header-only libraries is setting one up for severe disappointment. > > The standardized libraries are more header-only than Boost so am not sure how this isn't a rap on them also. Somehow C++ has become successful in spite of this. Brian Ebenezer Enterprises - In G-d we trust. https://github.com/Ebenezer-group/onwards

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