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[Histogram] Status of the review schedule
by Mateusz Loskot 11 Jul '18

11 Jul '18

Hi, Following some discussion in January this year, Hans Dembinski's Histogram library was scheduled for review in March. AFAICT, no review happened. What is the current status of the proposal? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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[geometry][units]
by Pranam Lashkari 11 Jul '18

11 Jul '18

I am trying to use boost.geometry with the integration of boost.units. What I want to do is store a coordinate point (e.g: Cartesian or spherical) which should be unit safe.(e.g a cartesian point with length unit meter should give error with cross product is done with cartesian point with length unit millimeter). For this I am using boost::geometry::model::point. Problems I am facing: 1. If I use something like boost::geometry::model::point<UnitClass, 3 ,boost::geometry::cs::cartesian> then all the operations like cross product and dot product will fail as units can not be multiplied and if we multiply then dimensions and units will change. 2. suppose I want to use spherical 3d coordinate then boost::geometry::model::point is cable accommodate only one type of class for all the underlying dimension(eg: distance, longitude and latitude). But in real case distance should be in length and longitude and latitude should be in angle unit. Is there any way to integrate boost.units with boost.geometry for the purpose I mentioned above. Thank you, Pranam Lashkari

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Boost.Graph depth_first_visit algorithm
by Brook Milligan 09 Jul '18

09 Jul '18

The documentation on the Boost.Graph depth_first_visit algorithm indicates that the first argument is a non-const reference to an Incidence Graph. See https://www.boost.org/doc/libs/1_67_0/libs/graph/doc/depth_first_visit.html. However, in contrast the code in boost/graph/depth_first_search.hpp only implements the function for a _const_ reference to an Incidence Graph. I can see that changing the graph structure mid-traversal is a problem, but I have use cases in which graph properties (not graph structure) must be changed along the traversal. Thus, it seems that a valid use case is for this algorithm to work as documented, i.e., on a non-const graph. The attached patch implements overloads for the non-const versions of depth_first_{visit|search}, including overloads for the dfs_visitor member functions. Is there some reason not to extend the implemented interface in this way to better agree with the documentation? Cheers, Brook

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Clang 600 and BOOST_SYSTEM_CONSTEXPR causes error_code.hpp compile failure.
by Paul A. Bristow 09 Jul '18

09 Jul '18

Having failed to build Boost libraries using Clang 6.0.0 using b2/bjam on Windows, I am now trying instead to use Codeblocks on Windows 10 to build static libraries. It comes to grief with these messages (the berbose gory details can be posted if anyone can help). In file included from I:\modular-boost\boost/system/system_error.hpp:14: I:\modular-boost\boost/system/error_code.hpp:409:88: error: variable does not have a constant initializer template<class T> BOOST_SYSTEM_REQUIRE_CONST_INIT system_error_category cat_holder<T>::system_category_instance; ^~~~~~~~~~~~~~~~~~~~~~~~ I:\modular-boost\boost/system/error_code.hpp:409:19: note: required by 'require_constant_initialization' attribute here template<class T> BOOST_SYSTEM_REQUIRE_CONST_INIT system_error_category cat_holder<T>::system_category_instance; ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I:\modular-boost\boost/system/error_code.hpp:392:44: note: expanded from macro 'BOOST_SYSTEM_REQUIRE_CONST_INIT' # define BOOST_SYSTEM_REQUIRE_CONST_INIT [[clang::require_constant_initialization]] ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This seems to be the ultimate cause I:\modular-boost\boost/system/error_code.hpp:226:41: note: non-constexpr constructor 'error_category' cannot be used in a constant expression BOOST_SYSTEM_CONSTEXPR explicit std_category( boost::system::error_category const * pc ): pc_( pc ) Is this because BOOST_SYSTEM_CONSTEXPR should not be defined? I note this in error_code.hpp #if defined(__GNUC__) && (__GNUC__ == 7 || __GNUC__ == 8) && __cplusplus >= 201700L // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83835 # undef BOOST_SYSTEM_HAS_CONSTEXPR #endif should this undef list also include clang, and if so which versions 600? Or is there something about Boost.config and Codeblocks on Windows? Adding unconditional # undef BOOST_SYSTEM_HAS_CONSTEXPR seems to work. Suggestions welcome. Paul --- Paul A. Bristow Prizet Farmhouse Kendal UK LA8 8AB +44 (0) 1539 561830

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toolset=clang-win uses clang-linux-win?
by Peter Dimov 09 Jul '18

09 Jul '18

When I try `b2 toolset=clang-win` on Appveyor, I get `clang-linux-win` instead, that is, `-win` is interpreted as version for some reason, not as platform: https://ci.appveyor.com/project/pdimov/system/build/job/sjpdq5yrir2ewuhh Is this normal, or is it a bug in the clang toolset? Is there a magic command line incantation that would let me select clang-win?

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[Boost Build] clang-win, <compatibility> property?
by degski 08 Jul '18

08 Jul '18

error: Please set <compatibility> property for visual studio version! How and to what value (VS2017 - 15.7.4, Compiler Version 19.14.26431 ) do I set the <compatibility> property using a project-config.jam file? The documentation <https://boostorg.github.io/build/manual/develop/index.html#bbv2.reference.t…> does not list clang at all, which probably means it works like gcc, there is obviously no <compatibility> property there. Help would be appreciated, then I can post some build results of 1.68-rc2. degski -- *"If something cannot go on forever, it will stop" - Herbert Stein*

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python::numpy not built on windows binary installers
by Nicholas Devenish 07 Jul '18

07 Jul '18

Hi All, I just downloaded the windows boost binaries from https://dl.bintray.com/boostorg/release/1.67.0/binaries/, linked from the boost downloads page. They are missing the boost_numpy library. This (silently) doesn't build if the python installation that boost finds is missing numpy. This is listed as "Third Party" so apologies if this is the wrong place to report it - but it's not clear from the page who makes them. I also couldn't find any mention of this, so don't know if it's a deliberate exclusion. Nick

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[release] Boost 1.68.0 Beta 1 Release Candidate 2
by Marshall Clow 07 Jul '18

07 Jul '18

The release candidates for the second 1.68.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.68.0.beta1.rc2/source/> The release notes are not yet available. The updated documentation is not yet available. [ They will be available in a day or two. ] == Changes since RC1: * version.hpp now has the correct version number in it. * Boost.Wave now builds on FreeBSD * Boost.ProgramOptions should now pass tests on msvc-10.0. The SHA256 checksums are as follows: 961d2bdc74c1499c931b32098842abba8883b1a89ef5c8f8f0ab0aff771a3ce5 boost_1_68_0_b1_rc2.7z 0364846258648e39908ca7cebfc2d2216eef6980c32aaf8276d2cfe73ef012e3 boost_1_68_0_b1_rc2.tar.bz2 d99105685a68907a76b0479ecde77915423246236ef0db9cb846c5bfc09b41f3 boost_1_68_0_b1_rc2.tar.gz 6158e0e961bfb0d8adeb2ea70337b08504668258025f0a873fb21eee3436d22e boost_1_68_0_b1_rc2.zip 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 Boost Release Managers

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[iostreams] Merging to master
by Edward Diener 07 Jul '18

07 Jul '18

I would like to merge the iostream changes on 'develop' to 'master'. They are all green on the 'develop' tests, and have been tested for awhile now, and I have just been lax getting these to the 'master' branch.

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[1.68.0 Beta1 RC1][iostreams][vs2017 preview] seekpos is not a member of std::pos
by Mateusz Loskot 07 Jul '18

07 Jul '18

Hi, I'm trying to build some of Boost libraries with the very latest VS 2017 Version 15.8.0 Preview 3.0 I've changed project-config.jam to point msvc-14.1 to the corresponding CL.EXE ``` using msvc : 14.1 : "c:\Program Files (x86)\Microsoft Visual Studio\Preview\Professional\VC\Tools\MSVC\14.15.26608\bin\HostX64\x64\cl.EXE" ; ``` In "x64 Native Tools Command Prompt for VS 2017 Preview", I do ``` .\bootstrap.bat b2 -j8 toolset=msvc-14.1 address-model=64 variant=release --with-iostreams ... compile-c-c++ bin.v2\libs\iostreams\build\msvc-14.1\release\address-model-64\link-static\threading-multi\file_descriptor.obj file_descriptor.cpp .\boost/iostreams/positioning.hpp(96): error C2039: 'seekpos': is not a member of 'std::fpos<_Mbstatet>' c:\Program Files (x86)\Microsoft Visual Studio\Preview\Professional\VC\Tools\MSVC\14.15.26608\include\iosfwd(132): note: see declaration of 'std::fpos<_Mbstatet>' ``` Is this expected? Shouldn't this be fixed by https://github.com/boostorg/iostreams/pull/57 ? Or the PR has not made it into the master? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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[Boost PP] MSVC PP Updated Info
by degski 07 Jul '18

07 Jul '18

More info <https://blogs.msdn.microsoft.com/vcblog/2018/07/06/msvc-preprocessor-progre…> . degski -- *"If something cannot go on forever, it will stop" - Herbert Stein*

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[release] Boost 1.68.0 Beta 1 Release Candidate 1
by Marshall Clow 07 Jul '18

07 Jul '18

The release candidates for the first 1.68.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.68.0.beta.1.rc1/source/> The release notes are not yet available. The updated documentation is not yet available. [ They will be available in a day or two. ] The SHA256 checksums are as follows: 4b39978aa227f56cc00715d48032e18f4bb259de756637a653b5acead4417e0b boost_1_68_0_b1_rc1.7z 39f6fdc16fc62041ca1401c5e8d1cd0220de24fd5d909eca3f0bf1049d1fd6f9 boost_1_68_0_b1_rc1.tar.bz2 9714d11a205e6f3a1cf1ed17b0caad8a64bc4a5459dfc6e1629e14e5e4b44dc7 boost_1_68_0_b1_rc1.tar.gz fe35f20eb5c2ebf5d4e4f15d0416e484058a732ca1a1e59b831b79d4d7702bdd boost_1_68_0_b1_rc1.zip 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 Boost Release Managers

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Error in ublas map_array doc
by Dick Hadsell 06 Jul '18

06 Jul '18

I was looking for a function to return the capacity of a Boost uBLAS map_array, so I checked the docs online. When I looked at this page: https://www.boost.org/doc/libs/1_67_0/libs/numeric/ublas/doc/index.html I found in the table of member functions two entries for the size() function, but one should clearly be the capacity() function. I confirmed in our headers that it exists. -- Dick Hadsell 203-992-6320 Fax: 203-992-6001 Reply-to: hadsell(a)blueskystudios.com Blue Sky Studios http://www.blueskystudios.com 1 American Lane, Greenwich, CT 06831-2560

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[release] 1.68.0 closed for Beta
by Marshall Clow 06 Jul '18

06 Jul '18

The master branch is now closed for all changes except by permission for the Beta release. Also, remember to add your libraries' changes to the release notes at: < https://github.com/boostorg/website/blob/master/feed/history/boost_1_68_0.q… > Thanks, -- The Boost Release Team

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[MultiIndex] Hinted insertion for multiple indices?
by Gareth.Sylvester-Bradley＠sony.com 04 Jul '18

04 Jul '18

Is there a way to provide insertion hints for multiple indices in a multi_index_container? In a particular example, I have a container with several ordered_non_unique indices, and for the majority of insertions, the value will end up at the end of these indices. I'm looking for a way to provide the index.end() hint for all of these indices? (Or maybe alternatively, to relax the stability/insertion-order guarantee?) Thanks, Gareth

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[ASIO] Clarification regarding socket release on Windows
by Gyorgy Szekely 04 Jul '18

04 Jul '18

Hi, The documentation (boost 1.67) of asio::basic_stream_socket::release() has the following remark: *This function is unsupported on Windows versions prior to Windows 8.1, and will fail with boost::asio::error::operation_not_supported on these platforms.* This is in accordance with the compiler warning I get when building my project (from asio basic_socket.hpp), and the runtime behavior: the native socket ownership is indeed retained by asio. For the IOCP backend! If I add the BOOST_ASIO_DISABLE_IOCP define to the build I still get the warning, but the release() appears to be working: the ownership is released and I can do whatever I want with the socket. My question: does the above comment apply only to the IOCP backend and I can use release() with the reactive socket service? Or it just happens to be working in my current setup but it's not guaranteed for others (or it leaks resources, etc...)? Regards, Gyorgy

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[beast] warning
by Vinnie Falco 04 Jul '18

04 Jul '18

I'd like to merge to master, this tiny fix for a warning: <https://github.com/boostorg/beast/pull/1175> The OSX build failure is spurious and unrelated Thanks

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Boost linked example
by degski 03 Jul '18

03 Jul '18

Could someone, please, point me to an example (in the Boost source, i.e. a file in the libs sub-folder) that would require (with certainty) a built library. Which library don't matter. I've tried some date-time examples and boost::random::random_device, but it works, while I hoped it wouldn't. The latter can also mean I have some strays, but then I know that. I would like to check vcpkg static-static linking for Boost. Thanks, degski -- *"If something cannot go on forever, it will stop" - Herbert Stein*

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CMT Library and CI Status for Boost 1.68.0
by James E. King III 01 Jul '18

01 Jul '18

I have been working on adding CI to the CMT libraries (and a few others). This provides improved quality and metrics for each repository with builds for various linux and windows combinations, as well as code coverage and static code analysis with coverity scan. Here is the current status for work that will make it into 1.68.0: The CI framework I have been adding is here: https://github.com/jeking3/boost-ci CI has been enabled on the following repositories (and any identified defects have been resolved) and is passing: function, mpl, pool, property_map, ptr_container, rational, tokenizer In addition, Boost.Move and Boost.Signals2 are also now using this framework to improve deliverable quality. CI not yet enabled on (and reasons): Boost.Assign fails to compile <https://github.com/boostorg/assign/pull/16> with MSVC 2012 in Appveyor. Boost.ConceptCheck fails to compile <https://github.com/boostorg/concept_check/pull/13> on most compilers in Travis CI and Appveyor. (It looks like it's unusable.) Boost.DisjointSets - status unknown (no CI) - open question still unanswered: Can we merge this into container? It is only used by graph and graph_parallel. Boost.DynamicBitset fails to compile <https://github.com/boostorg/dynamic_bitset/pull/23> on all MSVC and on linux with c++03 mode. Boost.Interval (numeric/interval) fails to compile <https://github.com/boostorg/interval/pull/14> - most combinations fail and may go into an infinite loop in some cases. Boost.Logic (tribool) uncovered issue #8 <https://github.com/boostorg/logic/issues/8>. Boost.Signals - we discussed a removal notification in an upcoming release but no action has been taken by the CMT yet to make this happen so it may slip into the next release. Boost.Statechart needs some Jamfile help to get it to work with this CI infrastructure. I am most concerned about Boost.ConceptCheck and Boost.Interval. Both may be unusable at this point. If folks have any spare cycles and care to take a look, it would be appreciated. Thanks, Jim

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[config] MSVC feature-test macros
by Stephan T. Lavavej 29 Jun '18

29 Jun '18

Hi Boost devs, FYI, VS 2017 15.8 Preview 3 has been released, with support for feature-test macros. If you want to take advantage of the feature-test macros, please notify me immediately about any problems so I can get them fixed for the production release. Notes: * __has_cpp_attribute is the one thing that isn't supported yet. * There are minor changes coming for the production release of 15.8, notably L suffixing and an increase in the value for __cpp_deduction_guides. * Library macros are defined by including any <meow> or <cmeow> header (but not <meow.h>). <ciso646> is the lightweight way to get all macros. This will be superseded by <version> in C++20, but that is not yet implemented. * The macros are always provided regardless of the /std compiler option. (Of course their definedness and values vary.) * We are defining __cpp_exceptions and __cpp_rtti, although those weren't picked up for C++20. * The only fundamentally new ability that these macros provide is the ability to sense whether thread-safe statics are supported; this was previously controlled by a compiler option, but not reflected in any MSVC-specific macro. * The macros respect all of our compiler options and library control macros - e.g. if std::byte's definition is suppressed (to avoid conflicts with the Windows SDK), then __cpp_lib_byte reflects that. Hope this helps, STL

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[chrono] #13557 Boost 1.67.0 chrono library Windows build installs NTFS junction
by Stephan T. Lavavej 28 Jun '18

28 Jun '18

Hi Boost.Chrono devs, I have some additional information about https://svn.boost.org/trac10/ticket/13557 . (Also tracked at https://github.com/StephanTLavavej/mingw-distro/issues/58 , it affects both MSVC and MinGW.) As Joshua Morrison discovered, copying libs/chrono/stopwatches/include/boost/chrono/. to boost/chrono before building is a workaround that prevents the junction and hardlink from being created. Also, I mentioned this on Twitter and René Rivera said: "Those links are supposed to appear only for the git checkout of @Boost_Libraries and are created on demand when headers are reference during the header scanning. Creating those for a release is a bug in the release process." (https://twitter.com/grafikrobot/status/1011077139511369728 ) I'm still not sure what the correct fix is, but it seems that boost/chrono should contain the stopwatches files, if they're being referenced by other headers. Thanks, STL

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[ Interest? ] [ out_ptr ] Tiny C++ Abstraction for C-Style Output Pointers
by ThePhD 28 Jun '18

28 Jun '18

Dear Boost Community, I was encouraged to submit this small library that I had created as a formal public investigation of the performance and API-interop benefits to the Boost Mailing List, to perhaps see if other people have come up with something similar to this at their own comapnies. out_ptr is a small abstraction for making types such as std::unique_ptr, std::shared_ptr, boost::shared_ptr, and the upcoming std::retain_ptr <http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0468r0.html> work work C-Style output functions as a parameter, addressing the need of wanting to be able to do "my_c_api_init( foo, bar, &my_smart_ptr );". It's design is meant to be extensible by both the library implementer and the user, enabling it to be used with other pointer types that do not originate from either `boost::` or `std::`. The library replaces the sought-after syntax of: my_c_api_init( foo, bar, &my_start_ptr ); with a free function that does not impose on the interface of the smart pointer: my_c_api_init( foo, bar, out_ptr( my_smart_ptr ) ); This makes it possible to use a temporary return value to give a reference to a pointer value that then performs a reset on the smart pointer. Is there any want for something like this? I know it has seen use at companies and Studios I have worked in and interacted with, including Microsoft and VMWare. std::retain_ptr's author also has a need for this to make interop easier with reference-counting C APIs and beyond, and I myself implemented something like it 5 years ago and have been using it ever since. Sincerely, JeanHeyd P.S.: this is also going to end up going in the Post-Rapperswil Standards C++ Mailing as well. The proposal is also contained in the repository: https://rawgit.com/ThePhD/out_ptr/master/papers/d1132.html

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[release] 1.68.0 closed for major changes
by Marshall Clow 28 Jun '18

28 Jun '18

The master branch is now closed for new libraries and breaking changes, and will be closing for the beta in one week. Also, if you're ready, you can also add your libraries' changes to the release notes at: <https://github.com/boostorg/website/blob/master/feed/ history/boost_1_68_0.qbk> After editing the release notes, you should get a form to create a pull request, remember to submit it, otherwise I won't see your change. Thanks, -- The Boost Release Team

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[Boost PP] MSVC PP
by degski 28 Jun '18

28 Jun '18

We seem to be getting there. Visual Studio 2017 version 15.8 Preview 3 Announcement <https://blogs.msdn.microsoft.com/visualstudio/2018/06/26/visual-studio-2017…> tl:dr: "*C++ Standards:* A new, experimental, token-based preprocessor that conforms to C++11 standards (including C99 preprocessor features), enabled with /experimental:preprocessor switch. This will be controlled with macro _ *MSVC*_TRADITIONAL, which will be defined to 1 when using the traditional preprocessor and 0 when using the new experimental standards conformant preprocessor." degski -- *"If something cannot go on forever, it will stop" - Herbert Stein*

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[release]
by Zach Laine 27 Jun '18

27 Jun '18

I'm seeing a difference in the Yap Quickbook build in a local checkout of boost-with-submodules, develop branch, and the Circle CI develop build. The auto-index seems to be wrong in the Circle CI one: https://www.boost.org/doc/libs/develop/doc/html/yap.html Note that the stuff at the bottom of that page refers to content in other libs. The Reference section also points to the wrong stuff in the .hpp detail pages. When I originally moved Yap over to Boostorg, I did not initially update all the paths correctly for an integrated Boost build; I was doing a standalone doc build. I have since fixed the paths, and I see the right index and Reference sections when I build locally. I suspect that the Circle CI cache has some files lying around that are causing this problem, but I don't really know. Does anyone have any insight into this problem? Does anyone have admin rights to do a Circle CI rebuild-without-cache? Thanks, Zach

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