August 2018 - Boost - lists.preview.boost.org

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

13 Aug '24

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

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[asio][coroutine] forbid_suspend blocks
by Vinícius dos Santos Oliveira 07 Aug '19

07 Aug '19

I've implemented a dumb linter using Python + clang API that allows you to mark certain blocks as “atomic in respect to coroutines” using C++11 attributes. Usage example follows: void f() { int yield; g(yield); [[bt::forbid_suspend]] { // Comment this call to make linter accept the code g(yield); t(); } } You can change bt::forbid_suspend to another identifier by tuning settings on the beginning of the script. The prefix forbid was inspired by Rust's linters[1] as you cannot disallow the linter from inside the forbid_suspend block. Some limitations follow: - A suspend point is identified by looking references to any id equals to yield in the last argument passed to function calls. It means that yield[ignored_ec] and alike will be correctly identified, but it needs to be named yield and it needs to be the last argument to the function call. - I haven't found a way to extract attributes related to COMPOUND_STMT nodes with clang API, so I manually look for token gaps and do a simple regex. It means you cannot use macros to [[bt::forbid_suspend]] as the macro won't be expanded. - You better call the script with '-x c++' and also ' -I/usr/lib/clang/5.0.1/include'. Like I've said in the beginning of the email, it's a *dumb* linter, which means it doesn't try to handle all cases. Therefore, I don't hope to do many changes to it or maintain it to work against newer releases of clang and I'm only uploading it to gist (not fullblow Github): < https://gist.github.com/vinipsmaker2/d930fbe5b7597432b021effe618da171>. It should also be easy to hack as it is very small. I'm releasing the linter under public domain. Enjoy. I have been using fibers in a daily basis on the last months of my job to solve networking problems on a gateway project. Some of the technologies I use are: - Boost.Asio and its spawn function. - A few custom synchronization primitives for the fibers (e.g. mutex, semaphore). - Eventually I'll have to write a custom spawn function that returns a joinable handle so I can kill the usage of a fiber::barrier in a few places. I've been using the linter for about a week already and looks fine. My use case are: - To prevent iterator invalidation in regions accessing shared variables. - To guarantee events order in algorithms that handle races (cannot yield while task YYY hasn't finished). The project I use it in is not an open source project, so I cannot talk much more about it. Also, I don't claim my solution is original. I wouldn't be surprised if the very same solution exists in the wild (please let me know if you know of a similar approach). This is not a new problem. It is know for some time. For instance, in P0171, Gor Nishanov noted this same problem: “In coroutines the suspend point is clearly marked with await, which tells the reader that something unusual happens in this function and allows the reader, for example, to confirm whether the lifetimes of the objects of interest align with the lifetime of the coroutine or not, whether some locks need to be acquired to protect some concurrently accessed data, and whether some locks need to be released before the execution reaches the suspend point.” — <http://open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0171r0.html>, 2015 However, the solution he presented was to manually examine whole blocks of code without help from the compiler. I argue that the solution he presented is as error-prone as manually looking for exit paths that don't free acquired resources in languages lacking RAII. And I've been spoiled too much by RAII. Furthermore, I take this comment of his with highly suspicious look: “Since we are on the subject of maintenance nightmares, we would like to offer a conjecture that the absence of the await in P0114 is a likely source of many maintenance nightmares. Without a syntactic marker to signal to the person reading the code that something funny is going on, it is impossible to tell whether the following code is correct or not” — http://open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0171r0.html If I had to give a vote to the proposal he was defending or Chris' proposal, I'd probably have chosen Chris'. [1] https://doc.rust-lang.org/reference/attributes.html# lint-check-attributes -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

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Re: [boost] [ Interest? ] [ out_ptr ] Tiny C++ Abstraction for C-Style Output Pointers
by Bjorn Reese 12 May '19

12 May '19

On 06/28/18 21:03, ThePhD via Boost wrote: > 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 Does out_ptr have other use-cases than C interoperability?

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clang-win, again
by Peter Dimov 31 Oct '18

31 Oct '18

Has anyone succeeded in getting clang-cl.exe working under b2? I've installed llvm-6.0.1, added it to PATH, put using clang-win : : : <compatibility>vc14 ; in my user-config, and what I get is: C:\boost-git\develop\libs\smart_ptr\test>b2 toolset=clang-win sp_interlocked_test warning: mismatched versions of Boost.Build engine and core warning: Boost.Build engine (b2) is 2015.07.00 warning: Boost.Build core (at C:/boost-git/develop/tools/build/src) is 2018.02-git C:/boost-git/develop/tools/build/src/tools\msvc.jam:1087: in set-setup-command *** argument error * rule virtual-target.from-file ( file : file-loc : project ) * called with: ( : /C:/boost-git/develop/libs/smart_ptr/test : object(project-t arget)@129 ) * missing argument file C:/boost-git/develop/tools/build/src/build\virtual-target.jam:970:see definition of rule 'virtual-target.from-file' being called C:/boost-git/develop/tools/build/src/tools\msvc.jam:652: in clang-win.compile.c+ + C:/boost-git/develop/tools/build/src/kernel\modules.jam:107: in modules.call-in C:/boost-git/develop/tools/build/src/util\indirect.jam:105: in indirect.call C:/boost-git/develop/tools/build/src/build\virtual-target.jam:902: in execute C:/boost-git/develop/tools/build/src/build\virtual-target.jam:821: in class@acti on.actualize C:/boost-git/develop/tools/build/src/build\virtual-target.jam:332: in actualize- action C:/boost-git/develop/tools/build/src/build\virtual-target.jam:518: in actualize- no-scanner C:/boost-git/develop/tools/build/src/build\virtual-target.jam:142: in class@virt ual-target.actualize C:/boost-git/develop/tools/build/src/build\configure.jam:258: in try-find-build C:/boost-git/develop/tools/build/src/build\configure.jam:396: in find-builds-raw C:/boost-git/develop/tools/build/src/build\configure.jam:455: in configure.find- builds C:/boost-git/develop\boostcpp.jam:734: in boostcpp.deduce-address-model C:/boost-git/develop/tools/build/src/kernel\modules.jam:107: in modules.call-in C:/boost-git/develop/tools/build/src/util\indirect.jam:105: in indirect.call C:/boost-git/develop/tools/build/src/build\property.jam:144: in property.evaluat e-conditionals-in-context C:/boost-git/develop/tools/build/src/build\targets.jam:1087: in evaluate-require ments C:/boost-git/develop/tools/build/src/build\targets.jam:1121: in common-propertie s2 C:/boost-git/develop/tools/build/src/build\targets.jam:1017: in targets.common-p roperties C:/boost-git/develop/tools/build/src/build\targets.jam:1313: in class@basic-targ et.generate C:/boost-git/develop/tools/build/src/build\targets.jam:812: in generate-really C:/boost-git/develop/tools/build/src/build\targets.jam:784: in class@main-target .generate C:/boost-git/develop/tools/build/src\build-system.jam:797: in load C:\boost-git\develop\tools\build\src/kernel\modules.jam:295: in import C:\boost-git\develop\tools\build\src/kernel/bootstrap.jam:139: in boost-build C:\boost-git\develop\boost-build.jam:17: in module scope

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[RFC] unique_val (handles, IDs, descriptors...)
by Miguel Ojeda 15 Oct '18

15 Oct '18

Hi all, While working on a medium-sized project, I had to wrap quite some handles, IDs, descriptors, etc. into RAII classes. Somehow, writing those and making them movable seemed more verbose than needed. I searched in the STL and Boost for something already implemented, but nothing seemed to come up. I decided to write my own prototype to see whether I was missing something important; but actually using it in my project felt quite natural and simple. At this point, I asked for a second opinion from a well-known expert (thanks Scott!) and he agreed that it seemed like a reasonable idea but, of course, he would also be surprised if others haven't come up with something similar. So I polished it up a bit and uploaded it to: https://github.com/ojeda/unique_val Below you have the introduction inlined [1]. If you have the time, please take a look (specially to the Rationale) and let me know your comments. The code itself is very short and straightforward. If you already have this class/template in Boost somewhere that I missed, please let me know! Otherwise, if you think this could be interesting to put into Boost in some existing library (not sure which) or as a new tiny library, I would be glad to make the effort to expand it, clean it up, etc. Thank you! Miguel [1] """ A single-header header-only library for representing unique values (handles, IDs, descriptors...) that default to a value on move for C++11, C++14 and C++17. It simplifies writing resource-owning classes (RAII) with move semantics support for resources with handles, IDs or descriptors that are supposed to be used as unique values, not as unique pointers. For instance, it can be used with non-pointer handlers (like the `int` file/socket descriptors in POSIX) and with opaque pointer handlers (like the `HWND` handles in the Win32 API). As such, it can be used as an alternative to `std::unique_ptr` with or without custom deleter, specially for resources that use a non-pointer type or resources that are not simply heap-allocated. It does not have any overhead compared to using the original type. It supports booleans, integers, pointers and enumerations. The default value can be different than the default-constructed value (i.e. different than 0, nullptr, etc.). """

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Tools to manage multiple repositories effectively?
by James E. King III 09 Oct '18

09 Oct '18

Hello, I am looking for tools that would allow me to create a portal and/or monitor the following properties of boost repositories. I am in the CMT and at least one fix that was in develop never made it into master for the 1.68.0 release, so I want to be able to see, at a glance, information about the boost repositories I care about in one place. There are about 20 repositories I regularly participate in now so a portal to show what I need to worry about would be useful. 1. How far behind is master (with respect to develop)? This would help identify which repositories are behind develop. Useful for ensuring things get into a release. 2. How many open pull requests? 3. How many new pull requests (within the last week)? 4. How many updated pull requests (within the last week)? 5. How many open issues? 6. How many new issues (within the last week)? 7. How many updated issues (within the last week)? "week" could be configured, perhaps month, or "since I last visited". Anybody know of any good tools or perhaps an existing site that can do this for a multi-repository solution? Thanks, Jim

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[all] Request for out of the box visibility support
by Antony Polukhin 09 Sep '18

09 Sep '18

I'd like to draw attention to a problem with Boost binaries for Linux. There's an awesome -fvisibility=hidden flag for Linux compilers that improves load times, performance, size of binaries and reduces the chance of symbol collisions. More info at https://gcc.gnu.org/wiki/Visibility . Unfortunately, most of the Boost libraries do not set it by default: - atomic - chrono - container - context - contract - coroutine - date_time - exception - fiber - filesystem - graph - graph_parallel - iostreams - locale - mpi - program_options - python - random - regex - signals - system - test - thread - timer - type_erasure - wave Moreover minority of the above libraries just do not work with the flag. Users just can not run ./b2 cxxflags="-fvisibility=hidden" because there's a chance that some library could stop linking. Actually things are even more ugly. Linux distributions usually do not tune the build flags for each package so at least Debian based distributions build Boost with default flags. Users get suboptimal builds. If you're a maintainer of one of the above libraries *please do* the following steps: * Make sure that all the public symbols are accordingly marked with appropriate BOOST_SYMBOL_* macro. Instruction is available here: https://www.boost.org/doc/libs/1_68_0/libs/config/doc/html/boost_config/boo… * Turn on the visibility=hidden by default: * by adding <target-os>linux:<cxxflags>"-fvisibility=hidden" to the Jamfile if you do not care much for antique compilers (Example https://github.com/boostorg/stacktrace/blob/819f2b1c861dec7530372a990ecabab… ) * by using a more advanced technique for detecting the flag availability (For example see https://github.com/boostorg/math/blob/develop/build/Jamfile.v2#L20 or https://github.com/boostorg/log/blob/develop/build/Jamfile.v2#L24 ) P.S.: I would appreciate any comments or updates on the feature request. P.P.S.: Log, Math, Serialization (and Stacktrace) libraries already use that flag by default. Many thanks! -- Best regards, Antony Polukhin

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[range] #11202: boost.sort header conflicts with boost.range header
by Steven Ross 07 Sep '18

07 Sep '18

https://svn.boost.org/trac10/ticket/11202 has been sitting for years. The "using range::sort" causing the namespace pollution needs to be deleted, and then everything depending on that inside boost needs to be fixed. This will break people dependent on the namespace pollution, but that's the only way to clean it up. Is anyone willing to take on this cleanup? Is there a good way to identify cross-library dependency breakages in situations like this so they can be fixed?

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Trac
by Robert Ramey 07 Sep '18

07 Sep '18

Could we agree to stop using the Trac system? The github issues/pr system is much more functional. I propose we close the trac system to new issues - be of course leave it available for reference. Robert Ramey

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Guidelines on copyright notice maintenance
by Mateusz Loskot 06 Sep '18

06 Sep '18

Hi, The license guidelines [1] include instructions on "How should Boost programmers apply the license to source and header files?" Unless I've missed it, there seem to be lack of guidelines about how to maintain (existing) copyright notices. I don't aim to resurrect the old lengthy thread from Sept 2015 on validity of copyright notices. In that thread, however, some guidelines or conventions were expressed: [2] "because copyright is only claimed for changes meeting a certain threshold of originality" [3] "It's up to those people to add a line if they so decide. Copyright only covers expressions of creativity." Those suggests, there seem to be common understanding on if/how/when it is recommended or even necessary to update copyright notice in a source file of a Boost library. Wouldn't it be helpful to captured those as guidelines in the BSL FAQ. Would there be someone knowledgeable about it and willing to make the update or at least explain it here? (I will make it into HTML and PR to boostorg/website) I understand David and Beman, primary authors of the page [1], may no longer be available. [1] https://www.boost.org/users/license.html [2] https://lists.boost.org/Archives/boost/2015/09/225565.php [3] https://lists.boost.org/Archives/boost/2015/09/225570.php Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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[ublas] Supporting DNNs with Tensors/Multidimensional Arrays
by Cem Bassoy 06 Sep '18

06 Sep '18

Gsoc <https://summerofcode.withgoogle.com/organizations/4507228564881408/> 2018 just ended one week ago and we had many successefully completed student projects <https://github.com/BoostGSoC18>. I was responsible for adding tensor support to Boost.uBLAS for primarily supporting multilinear algebra operations in the field of numerics. The wiki description along with the implementation can be found here <https://github.com/BoostGSoC18/tensor>. Similar to Boost.multi_array <https://www.boost.org/doc/libs/1_68_0/libs/multi_array/doc/index.html> the runtime-reshapable tensor data structure is parametrized in terms of number of dimensions (rank/order), dimension extents, data type, layout (first- and last-order) and storage type. The first two are runtime-variable. I am also about to add subtensor (view/handle of a tensor) along with multidimensional iterators for convenient algorithm implementation. It is yet not as flexible as GSL's multi_span <https://github.com/Microsoft/GSL/blob/master/include/gsl/multi_span>: does not yet support static rank and dimensions. However, basic generic tensor operations (contraction/transposition/reshaping/...), including a nice syntax for Einstein's summation convention with placeholders, using C++17 features are provided. The operations are evaluated using expression templates (not smart yet). Similar to the tensor <https://eigen.tuxfamily.org/dox/unsupported/group__CXX11__Tensor__Module.ht…> framework of Eigen, that is used by tensor flow <https://github.com/tensorflow/tensorflow>, the tensor data structure in Boost.uBlas could be taken for implementing deep neural networks or higher-order statistics I think. I am not sure if the C++ community would appreciate if Boost has some form of basic operations for building *deep neural networks* (DNNs). I would like to ask 1. if it make sense for boost to support basic operations for DNNs? 2. what are the obligatory, necessary basic operations for creating DNN building blocks? 3. if there are any additional data structure parameters that needs to be added for (efficiently) supporting DNNs? Best, Cem

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No Viable function warning
by randydom 03 Sep '18

03 Sep '18

Hello i've the bellow function : __declspec(dllexport) int TrySendData(_isocket * isocket,char * ibuff,int ilen) { boost::system::error_code ignored_error; boost::asio::write(isocket->socket(), boost::asio::buffer(ibuff,ilen), boost::asio::transfer_all(), ignored_error); if(ignored_error) return 0; return 1; } I get a *No Viable function* warning , can someone tells me why or helps me in fixing this warning . Thank you . -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Dev-f2600599.html

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Original STL Library Documentation has been recovered and is now safe forever.
by Robert Ramey 02 Sep '18

02 Sep '18

The Standard Template Library is the foundation of modern C++. The creation and publication of this code and its documentation set a new standard for the formal specification of what a computer program should do, how it should be designed and how it should be formally documented. These pages were maintained first by Silicon Graphics and then later by Hewett-Packard. In January of 2018 these pages were removed by H-P. This is a historic blunder. I have recovered the original STL Library Document and hosted them here: http://www.rrsd.com/software_development/stl/index.htm Robert Ramey

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[integer] CMT assume responsibility for Boost.Integer?
by James E. King III 01 Sep '18

01 Sep '18

The maintainer of Boost.Integer has no commits since 2008, and I was unable to get a hold of him by email (waited 10 days for a reply). I suggest we transfer responsibility of this repository to the CMT. - Jim

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Gsoc 2019
by Shubham Verma 01 Sep '18

01 Sep '18

Hey I'm new, but I'd like to contribute to your organisation, can someone please guide me along?

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Let's stop distributing binaries
by Robert Ramey 31 Aug '18

31 Aug '18

The fact is that users of boost use compilers with differing levels of C++ standard conformance. This creates a number of problems including (but probably not limited to) a) Using libraries built with different levels of C++ conformance may create ABI issues. b) it creates a discussion about "dropping C++03 support". Actually it creates a discussion about that the above actually means. c) It's motivated a suggestion that all libraries move to header only. This is not great idea - but I won't address that here. I believe all these issues - and more - would disappear if we just stopped distributing binaries. Each user would be building his own boost version with (presumably) the same compiler. Since C++03 compatible libraries are C++?? compatible, each library author can maintain the level of backward compatibility that he wishes. But if we're not going to distribute binaries, then users might as well just clone the latest "certified - good - tagged" version in the master branch from the github repo. That is, let's just stop or truncate the whole release circus. Replace with an occasional "certification/versioning procedure" which would make available a "squashed" master suitable for efficient cloning. This would make everyone's life easier. Robert Ramey

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A possible date for dropping c++03 support
by Mike Dev 31 Aug '18

31 Aug '18

Sorry for all the bad line-breaks in my previous message. I don't have access to a properly configured email client right now. This should be easier to read: ====== Original Message ============== Please, let's not derail the discussion just after some consensus has emerged and just before it actually produces actionable items. Let's not make the better the enemy of the good here. I made the suggestion to commonly drop c++03 support in the hope that it would actually lead to some code simplifications and reduced coupling between the boost libraries - even if only in their implementation (if someone wanted to do a real c++14 reboot of their library, no one is/was stopping them anyway). >From the survey, I'd say interest in actually applying c++11 features in libraries that a currently supporting 03 is already relatively low, but big enough that I believe this will actually lead to some changes other than just changing the default test settings. That is with a standard almost universally supported by compilers in use today. Even though the move from 11 to 14 is much less dramatic, c++14 support is less wide spread and outside of the big three, there are many compilers where even the most recent version doesn't support c++14, so I just don't see people that are currently maintaining c++03 support in their libraries suddenly starting to use c++14. All this doesn't preclude a discussion about if and when to move to c++14 or a general policy about LTS versions and the like, but please keep it separate unless you are really, really confident it will lead to something actionable earlier than what is currently proposed. I have lots of Ideas, how boost could be reformed and/or modernized but in the end it comes down to convince the individual library maintainers to actually do something. I think the current proposal will at least spark some action. Let the announcement to move to cmake be a warning sign about realistic expectations about the evolution of boost. Maybe I'm aiming too low, but again, if you want more, please open a separate thread and most likely, whatever you come up with there will not be mutually exclusive with what is proposed here. Regarding the test settings: If c++11 is supposed to be the lowest official supported version then that is what should be tested Anything else doesn't make sense (you can't claim to support c++11 if you don't test if it actually works there). In any case, as was mentioned before, for the announcement itself we don't need give any specifics about something that is going to happen 1-1,5 years from now. How about something like " c++03 mode/compilation will no longer be tested / part off the general test/suit"? Best Mike

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A possible date for dropping c++03 support
by Mike Dev 31 Aug '18

31 Aug '18

Please, let's not derail the discussion just after some consensus has emerged and just before it actually produces actionable items. Let's not make the better the enemy of the good here. I made the suggestion to commonly drop c++03 support in the hope that it would actually lead to some code simplifications and reduced coupling between the boost libraries - even if only in their implementation (if someone wanted to do a real c++14 reboot of their library, no one is/was stopping them anyway). >From the survey, Id' say interest in actually applying c++11 features in libraries that a currently supporting 03 is already relatively low, but big enough that I believe this will actually lead to some changes other than just changing the default test settings. That is with a standard almost universally supported by compilers in use today. Even though the move from 11 to 14 is much less dramatic, c++14 support is less wide spread and outside of the big three, there are many compilers where even the most recent version doesn't support c++14, so I just don't see people that are currently maintaining c++03 support in their libraries suddenly starting to use c++14. All this doesn't preclude a discussion about if and when to move to c++14 or a general policy about LTS versions and the like, but please keep it separate unless you are really, really confident it will lead to something actionable earlier than what is currently proposed. I have lots of Ideas, how boost could be reformed and/or modernized but in the end it comes down to convince the individual library maintainers to actually do something. I think the current proposal will at least spark some action. Let announcement to move to cmake be a warning sign about realistic expectations about the evolution of boost. Maybe I'm aiming too low, but again, if you want more, please open a separate thread and most likely, whatever you come up with there will not be mutually exclusive with what is proposed here. Regarding the test settings: If c++11 is supposed to be the lowest official supported version then that is what should be tested Anything else doesn't make sense (you can't claim to support c++11 if you don't test if it actually works there). In any case, as was mentioned before, for announcement itself we don't need give any specifics about something that is going to happen 1-1,5 years from now. How about something like " c++03 mode/compilation will no longer be tested / part off the general test/suit"? Best Michael

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A possible date for dropping c++03 support
by Mike Dev 30 Aug '18

30 Aug '18

>From the discussion about abi compatibility when the Boost.System library is compiled e.g. in c++03 mode and then included in ac++11 project or vice versa (https://groups.google.com/forum/#!topic/boost-developers-archive/EWG5NVOZo_ g) > > When can we drop C++03 support? :D This will probably be ignored or shouted down, but maybe someone just needs to make a concrete suggestion about which people can discuss and vote so I'm giving it a shot: What about the first or second release in 2020 ? By then, all major toolchains have had solid c++11 support for at least 5 years ( I think, msvc was the last one with VS2015) and at least partial support for 7+ years (gcc 4.8, msvc 2013, clang 3.3). Also, most likely c++20 will be released in that year, which means that c++03 compatible libraries would have to support 5 different (and partial incompatible) language versions by then (not to mention ABI-compatibility considerations between different versions). That should also be enough time to ensure that the last c++03 release (late 2019) is really solid (for projects that still can't upgrade to c++11) and ideally there could be a few more bugfix-releases afterwards as is often done by other software projects. And before someone starts to raise straw mans: That of course wouldn't mean that a particular library *must* no longer compile in 03 mode, but one can no longer rely on the boost-internal dependencies remaining c++03 compatible. Best Mike

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[ptr_container] associative container insert takes reference instead of const reference as key ?
by comic fans 30 Aug '18

30 Aug '18

Hello , I've found that ptr_unordered_map.insert has following signature (from code and latest doc) std::pair<iterator,bool> insert( key_type& k, T* x ); that forbids calls like ptr_unordered_map.insert( myobj->id(), myobj) ,I wonder if this is by design , or some other reason ? why other overload takes const key_type& k as key type? and insert always call insert_impl which have const reference as key type ? any help would be appreciated.

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c++03 library survey
by Mike Dev 29 Aug '18

29 Aug '18

Hello everyone, this is closely related to the thread about "A possible date for dropping c++03 support" (https://groups.google.com/forum/#!topic/boost-developers-archive/i4UM-GfNu8w) but this is NOT meant as a vote on the suggestion, and I'd ask you to keep discussions to that thread. For the actually important part, please scroll down to the double line (===) For reference however, my suggestion was that c++03 support is officially dropped somewhere around early 2020 across all of boost. Which would mean, that from then onwards any library author could start to unconditionally use c++11 features in his library without prior announcement or transition period, even if other boost libraries that currently support c++03 have a dependency on it. (Again, if you have questions or comments about this, please answer on the other thread) Somewhat late, I realized I first should have asked if / how much actual interest there is from the side of the library maintainers in the first place, because whatever the majority of the people on the ML thinks, it obviously won't have any effect if the actually affected people don't have any interest in using c++11 in the first place. Full disclosure: I'm not a boost contributor myself (at least nothing significant) but as a user, I have an interest in boost libraries becoming simpler, less entangled with each other and providing less types that are redundant in c++11 and later. You could call that more lightweight but that is a different topic. So, to get some idea if there is any interest in this topic, I'd ask each maintainer that is currently maintaining a c++03 compatible library to answer the following questions: =======Please quote from here ====================================== - Which library/ies are you maintaining? (I assume this isn't some sort of private information - otherwise ignore the question) - Would you like to unconditionally use c++11 features if you would not have to worry about this breaking boost internal users? - Would you like to unconditionally use c++11 features if you would not have to worry about this breaking any users? - Would you deprecate your library completely if there were no boost-internal users and your current dependencies required c++11 (e.g. because your library has been merged into the c++11 standard library anyway) - Are you yourself using any boost library (in an up-to-date version) in a c++03, non-boost project? - Do you have any Idea if the latest versions of your library is used by any important/significant number of c++02 projects? [It is only important if *you* consider those projects important and or the number significant] =======Please quote till here ====================================== Note: When I'm talking about breaking users I mean breaking due to requiring c++11 compiler, not because you completely rewrite the API based on new c++11 idoms - that would probably better be done in a completely new library. Best regards and thank you for your time Mike

15 32

Re: [boost] A possible date for dropping c++03 support
by Glen Fernandes 29 Aug '18

29 Aug '18

Edward Diener wrote: > Other than not removing useful Boost libraries which support c++03 as > well as all subsequent C++ standard levels, and not telling people that > they can not use such libraries in c++03 mode if they actually want to > do so, I am perfectly willing to let others, including yourself, decide > the best way in which support for c++03 in Boost is reduced. My argument > has always been that putting a generalized statement on the website, > without explaining what it actually entails as far as using Boost l> ibraries is concerned, is going to lead to confusion and puzzlement > from end-users and endless questions. What can it possibly cost to > actually explain of what "Boost dropping support for c++03" actually > consists, when it is finally decided what Boost is going to do in this > area ? If it is a matter of correct grammar or exposition in the > explanation, I will gladly volunteer to write it if no one else wants to > do so. +1. It sounds like what we're going to communicate to users is that Boost library authors or maintainers are no longer required to make their libraries support C++03. Which sounds fine to me. I don't think library maintainers should be confined by users (even if the users are other Boost libraries) if they don't want to be. Any Boost library maintainers that wish to continue supporting their C++03 users will do so. Any other Boost library maintainers that depend on such libraries can drop the dependency on those libraries. Glen

3 3

Re: [boost] A possible date for dropping c++03 support
by Glen Fernandes 29 Aug '18

29 Aug '18

James King wrote: > I thought Peter Dimov got it right from the comment I saw earlier. > The project would no longer spend time and effort on qualifying or testing > C++03 compatibility. CI builds and the test matrix would no longer > specifically test C++03. The default language level for b2 builds would be C++11. Sounds right. All of these above is a much more useful statement to make to users. > Individual repository maintainers could attempt to continue to qualify > for C++03 however once an upstream dependency begins to include > C++11 code, that effort would have to give way. If an upstream dependency only works in C++11 and above, and the library maintainer wants to support C++03, they can either: A) Drop the dependency and still support C++03 B) Drop C++03 support But again it will be up to that library maintainer. > As a developer both working on and > consuming boost I would appreciate the permission to start using C++11 > without fear. You will be able to start using C++11 in the libraries that you maintain, without fear. You won't be able to force another library maintainer to let you use C++11 unconditionally in their library if they want to support C++03 users. Glen

1 0

BOOST_FOREACH on a filesystem directory_iterator?
by Peter Dimov 29 Aug '18

29 Aug '18

Boost.Filesystem apparently contains support for BOOST_FOREACH: https://github.com/boostorg/filesystem/blob/5a93351bfdf859ee47245e042973922… But it doesn't work: #include <boost/filesystem.hpp> #include <boost/foreach.hpp> namespace fs = boost::filesystem; int main() { fs::directory_iterator it; BOOST_FOREACH( fs::path const& p, it ) { } } 1>c:\boost-git\develop\boost/range/end.hpp(48) : error C2039: 'end' : is not a member of 'boost::filesystem::directory_iterator' The fix is trivial, but I wonder... how did nobody notice? Is this feature never used?

2 1

Future of the MaybeBoost Hash Library
by Ilia K 29 Aug '18

29 Aug '18

Hi! I was looking for a header-only library to compute SHA512 and found a very interesting project: The MaybeBoost Hash Library ( https://www.cs.mcgill.ca/~smcmur/hash/) that implements SHA/MD5 ect. In 2010 there was a discussion ( http://boost.2283326.n4.nabble.com/rfc-Preliminary-Hash-Library-td2668722.h…) about making it one of the Boost subprojects but nothing happened. Maybe some of you guys know what's the matter? -- - Ilia

2 1

Re: [boost] A possible date for dropping c++03 support
by Glen Fernandes 28 Aug '18

28 Aug '18

Peter Dimov wrote: > Edward Diener wrote: > > Peter Dimov wrote: > > > If I post "Boost is dropping support for C++03" f.ex. on Twitter or > > > Reddit, every single user will immediately understand what that means. > > > :-) > > > > I am not a participant of either so some of your humor is lost on me, but > > I can guess that it suggests that you do not consider the intelligence of > > the average Twitter or Reddit participant to be very high. > > No, that's not at all what I meant. I meant what I said. Users will > immediately understand "Boost is dropping support for C++03". I doubt hat. After the "Boost is moving to CMake" announcement on Reddit, I have a different interpretation of what Reddit will understand from "Boost <anything>". We should do things first, then announce that we've done them. Glen

2 1

1.68 Getting Started links to 1.67
by Olaf van der Spek 28 Aug '18

28 Aug '18

Hi, > The most reliable way to get a copy of Boost is to download boost_1_67_0.7z or boost_1_67_0.zip and unpack it to install a complete Boost distribution.1 1.67? Actually the best way is to use vcpkg if possible (IMO). https://www.boost.org/doc/libs/1_68_0/more/getting_started/windows.html -- Olaf

6 18

Add an adapter to cover fast bit functions
by Evgeny Shulgin 28 Aug '18

28 Aug '18

Hi all, some days ago I opened a thread about DynamicBitset[1] (where I noted that a small piece of code may double the speed of a function), which received some interesting answers (you guys rock!) I looked deeper and realized that Boost doesn't have functionality to do common bit operations *really* fast. Let me explain - there are several places in Boost where we needed to solve typical tasks connected with bits in integers - like "get log2 of an integer rounded down" or "get the number of trailing zeros" or "count number of 1-bits", and Boost contributors have been inventing there a wheel everywhere, with varying degrees of optimality: [2] - [6]. Moreover, if a programmer writes a cross-platform app and has to do smth with this stuff, it's likely that for bit operations he will write a "naive" implementations - e.g. getting the log2(x) for O(log N), when it could be done for O(log log N), but with a more complicated code. Also, as well as "smart" algos, there are other methods to use - precalced tables, taking a small additional memory when needed [6], and intrinsics (that are CPU-specific). Combining of these methods (intrinsics when conveniently, or tables/algos) gives a notable shift in performance - here's my benchmark [7] from my tiny library [8]. Performance here varies from *9.2%* to *36.9%* of speed of related naive functions. I can tell you a usercase - as a hobby I'm writing a chess variants engine (where bitsets used to represent chess board, and its size is *not* fixed to 64), and bit operations' speed there is a matter of life and death. So, what do you think of an adapter header in Boost, covering all these operation of all integer types (and maybe some other one-liners like `is_bit_set(x, pos)` ), which keeps programmers out of platform specifics? It may look as smth like this [8] (I wrote only 3 functions, but it's enough to show the potential). I guess it can be placed somewhere to *Boost.Algorithm*, and supported with CI build tests of different platforms. P.S. The (incomplete) list of bit functions, that will give a *notable* better performance compared with naive algos and even some "smart" (because of precalc/intrinsics): - count of bits - parity of bit count - first 1-bit - last 1-bit (aka integer_log2(x)) - leading zeros - trailing zeros - swap(x) - returns x with the order of the bytes reversed; for example, 0xaabb becomes 0xbbaa. (bytes here are 8 bits exactly) - rotate_left(x, shift) - rotate_right(x, shift) Other functions may look like `is_set(x, pos) -> return x & (1 << pos)` and aren't so interesting. [1]: https://lists.boost.org/Archives/boost/2018/08/242825.php [2]: https://github.com/boostorg/integer/blob/develop/include/boost/integer/inte… [3]: https://github.com/boostorg/move/blob/develop/include/boost/move/algo/detai… [4]: https://github.com/boostorg/dynamic_bitset/blob/develop/include/boost/pendi… [5]: https://github.com/boostorg/integer/blob/develop/include/boost/integer/comm… (really almost the whole file) [6]: https://github.com/boostorg/dynamic_bitset/blob/develop/include/boost/detai… [7]: https://gist.githubusercontent.com/Izaron/8c94b76818393ffd93613d255033bb48/… [8]: https://github.com/Izaron/bit_algo/blob/master/include/bits.hpp

5 6

A possible date for dropping c++03 support
by Mike Dev 28 Aug '18

28 Aug '18

> -----Original Message----- > From: Glen Fernandes <glen.fernandes(a)gmail.com> > Sent: Tuesday, August 28, 2018 1:25 AM > To: mike.dev(a)gmx.de > Subject: Re: [boost] A possible date for dropping c++03 support > > On Mon, Aug 27, 2018 at 1:10 PM Mike Dev <mike.dev(a)gmx.de> wrote: > > Conditionally using a c++11/14/17 feature is (usually) not the problem > > although there are sometimes pitfalls as Peter mentioned. However, it also > > has limited utility. E.g. it doesn't make sense to simplify a function > > implementation using c++11 features like auto, range based for, decltype, > > constexpr instead of TMP, if you have to maintain the c++03 code path as well. > > In principle, you could conditionally get rid of some boost dependencies > > in c++11 mode, but again at the cost of maintaining two different code > > paths (as boost types often have slightly different semantics from c++11). > > So why do it? And you still can't deprecate the dependency itself because > > it is still needed in c++03 mode. > > Why do it? I do it when it provides some benefit to the users: > > e.g. If alternative implementation using C++14 constexpr results in > faster compilation for users. > If supporting C++11 move semantics results in better performance > for the users. > If supporting C++11 variadic templates results in a more > flexible interface for the users. > > i.e. If I'm the maintainer, and I'm happy to have that burden of > maintenance, why does anyone else care that I support > C++03/C++11/C++14 users, in addition to C++17 users? > > Yes, these are the high value proposition cases, that you mention. > > There's also no dependency to the user is there?. e.g. If a library > obtain std::addressof from <memory> in C++11 mode and doesn't source > it from Boost.Core, to the user, the library doesn't depend on > Boost.Core. > > > So except for cases with a very high value proposition (move semantics, > > simplified api, c++11 only functionality) or simple annotations (noexcept, > > override) using c++11 features *conditionally* is usually not all that > > beneficial. My hope here is that at some point, those boost libraries > > will finally start to use c++11 features *unconditionally* in order to > > simplify things - not add even more complexity in the form of conditional > > compilation. > > Simplify things for which party? Are you worried about users or Boost > library authors/maintainers? I don't see how users are inconvenienced > unless the user wants some feature only available in later C++ modes > that the library maintainer refuses to implement. > > Glen There are (at least) three problems: 1) Not all dependencies are private. If a library e.g. uses boost::function in its interface (in particular if it returns one) the user is also directly affected by changes to that dependency. 2) As you know, the c++ compilation model is incredibly leaky, meaning transitive dependencies are not hidden from the user. E.g. if you are using boost core in your header and I include it, I do get all the symbols (including macros) in my TU too. Boost has (usually) very good hygiene, so the main problems here are usually compilation times, sometimes code size and tools (code highlighting, static analysis, refactoring etc.) that either get slower or totally break e.g. because they don't have a perfect emulation of the compilation environment and don't know which code paths are the currently active ones or are just not able to understand all the TMP. 3) Not every library in boost is as well maintained as yours and I as a user prefer "cleaner / simpler" libraries because they a) tend to have fewer bugs, b) I can more easily modify things myself if necessary, c) the easier the life of the maintainer, the more likely he has time to add new functionalities. Finally, if boost can deprecate and at some point even remove some libraries, then their maintainers (in particular the CMT) can focus their time on different projects. Btw.: In case this was not clear: I'm not a boost contributor myself and for some time now, we (as in our company) are actively trying to avoid boost dependencies for various reasons that have more to do with boost-internal stuff and the boost eco system than with e.g. inconvenient interfaces. So yes, at least some end-users do really care about the internals of boost. But admittedly, I mostly work on (semi-) embedded projects where we have to compile (and on rare occasion even modify) boost ourselves - not sure how common that is. Best Mike

3 3

[gil] Template instantiation with GCC 8 is 50x slower than with clang++
by Mateusz Loskot 26 Aug '18

26 Aug '18

Hi, One of Boost.GIL users reported very long compilation times with GCC 7 and 8 https://github.com/boostorg/gil/issues/131 then, reproduced the problem with a minimal example without Boost GIL and MPL dependencies. The issue has been reported to GCC developers - I think users/developers of other Boost libraries may be interested too https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87107 Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

1 0

[dynamic_bitset] Using of GCC built-in functions may increase performance of some methods
by Evgeny Shulgin 26 Aug '18

26 Aug '18

Hi all, when I was playing around the Boost.DynamicBitset library, I noticed the last lines of the count() function (which returns the number of bits in the bitset that are set): return do_count(m_bits.begin(), num_blocks(), Block(0), static_cast<value_to_type<(bool)mode> *>(0)); Well, this line was modified 10 years ago last time. Let's go deeper. GNU C provides several language features not found in ISO standard C. These include a bunch of bit operations - you can look at them here: https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html. For example, *__builtin_popcountll *counts the number of bits in an 'unsigned long long', so we can use this kind of code to calculate bits (don't judge, I wrote this fast and didn't think of coding standards): size_type res = 0; for (size_type i = 0; i < m_bits.size(); i++) { res += __builtin_popcountll(m_bits[i]); } I checked that m_bits[] and popcount() both work with 64-bit values on my machine. It halved the running time of a program that has a bitset and calls count() over and over again - here's the code <https://gist.github.com/Izaron/5005fed4184ee6483699191dc5ef3677> I used. These __builtin_XXX functions can be used everywhere where it's possible, with preprocessor directives. Or is it actually used and longer time means something else? I used the latest version of Boost.

6 8

[test][pull#151] Fix warning: BOOST_CLANG is not defined, evaluates to 0
by Mateusz Loskot 26 Aug '18

26 Aug '18

Hi, I've submitted a tiny fix for this annoyance: https://github.com/boostorg/test/pull/151 May I ask the library maintainers to merge it? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

2 1

GNOME outreachy
by Pranam Lashkari 26 Aug '18

26 Aug '18

GSoC just finished and it helped grow the community by adding few new students and maybe mentors to our Boost community. I was hoping why don't we also apply for GNOME outreachy also it is also similar to GSoC and can also help our community to grow. and by appearing in end of year internship in GNOME outreachy we can keep a flow of new contributors and motivate people to contribute to opensource throughout the year. Thank you, Pranam Lashkari

14 26

[regex] Drawing attention to link issue
by Antony Polukhin 24 Aug '18

24 Aug '18

Hello, The build flags for shared libraries are changing right now in b2. See https://github.com/boostorg/boost/pull/190 for more info. The thing is that Boost.Regex fails to link with those new flags, probably because of the https://github.com/boostorg/regex/issues/49 issue. If there's no simple solution for the above case, then please merge the https://github.com/boostorg/regex/pull/66/ . It should help. Thanks in advance!

2 2

[MSM] Still maintained?
by Christophe Henry 24 Aug '18

24 Aug '18

>Hi Boost-list, > >because I realized that my simple PR for Boost.MSM [1] (which makes it >compilable with C++17) and an even older one did not receive any >attention, I wonder if Boost.MSM is still actively maintained. > >The latest changes seem to be from around December 2017. > >Does anyone know, if Christophe is still active? > > >Best regards, >Deniz Hi Deniz, Sorry, I didn't have time to do it before vacations, I only merged your change to develop now. Thanks, Christophe

2 1

[type_traits][core] modularisation and moving stuff about (again)
by John Maddock 23 Aug '18

23 Aug '18

So... I have a couple of PR's to move some of type_traits into config so it can be used by core. It's a modest proposal so I can go with that I guess... but this moving stuff about all over the place just to satisfy dependencies does wind me up a bit - I know that I sometime struggle to figure out where stuff is on Github - half of Integer is in Config for example. How on earth would an end user figure that out in order to file a PR or a bug report? I know... "calm down dear" and all that ;) So radical suggestion - does type_traits just belong in core and lets be done with it? What would happen to the file history if we moved it (can I still "git blame")? DARFC, John. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

5 16

Re: [boost] [type_traits][core] modularisation and moving stuff about (again)
by Glen Fernandes 23 Aug '18

23 Aug '18

Andrey Semashev wrote: > I would rather encourage people use type traits, the official > interface. Boost.Config or Boost.TypeTraits could provide macros that > allow users to detect whether is_final is emulated or is the real > deal. One thing about this suggestion: If Boost.Config was to provide macros that tell users whether Boost.TypeTraits' boost::is_final<T>::value is emulated or the real deal, then the compiler detection logic currently in Boost.TypeTraits for detecting __is_final would already have to be duplicated in Boost.Config. That does not sound like a great idea. Right now TypeTraits provides both, which is better. i.e. It provides boost::is_final<T>::value and BOOST_IS_FINAL(T). The former uses the latter if it is defined, or is always false if not defined. If BOOST_IS_FINAL(T) and all its compiler detection logic lives in TypeTraits, then that all that compiler detection logic should not be duplicated in Config to provide a BOOST_HAS_IS_FINAL_INTRINSIC or similar feature detection macro. Glen

5 13

[test] I want my core dumped
by Alain Miniussi 22 Aug '18

22 Aug '18

Hi, I have assert in my library code, but when the assert fire in a test, the main function in minimal.hpp intercept the signal and explains that, yes, you asked for an abort, but no: [...] ../../../boost/test/minimal.hpp(136): exception "signal: SIGABRT (application abort requested)" caught in function: 'int main(int, char **)' Is there a way to avoid that behavior ? I need that core file. Thanks Alain

3 2

[multiprecision] Design question on variable precision types.
by John Maddock 22 Aug '18

22 Aug '18

Folks, I have a tricky design question that Boost.Multiprecision has been dodging relating to variable precision types - these have just expanded somewhat now that we support complex numbers via mpc as well as mpfr's reals etc. The basic use case is this: We have a set of numbers at very high precision, some calculations are performed on those directly, others we want to temporarily drop precision, get an approximate answer and perhaps later refine it. Generally speaking, performance trumps everything, on a really long running calculation 10-20% speedup can actually make a big difference (in $$'s in some cases if the CPU time is from the cloud). Up till now Boost.Multiprecision has been dodging this issue - it's actually pretty hard to program in a sane and consistent way, so the message has been "don't mix precisions" when using a type like boost::multiprecision::mpfr_float - just set what default you want and get on with it. But we really should do better than that. So... with the help of Danielle Brake I've been trying to nail this down in develop, what we have at present is: * Copy construction or move assignment copies the precision of the source. * Regular assignment retains the precision of the target variable. This is efficient in that assignment doesn't reallocate to a new precision, and provides an easy way to up/down sample precision when required. But it breaks equality after assignment. It does match what MPC/MPFR do in mpfr_set etc though. The fact that move assignment behaves differently from regular assignment bother me too - it's too easy to write code that triggers move semantics without noticing. The trouble is, being able to assign while retaining precision of source is sometimes useful too, so having move-assign behave differently provides a useful back door, but maybe one that's just too cute for it's own good? And then.... we get on to arithmetic. * Currently temporaries are created at current default precision. So it's easy to shoot yourself in the foot by not noticing that temporaries are being created in an expression and not having the default precision set correctly. I actually think this one might be solvable, but it's a huge job involving banning default constructors in all the backends to our number types, and then catching all the cases where they might have been used. * What should happen in "a = expression", where the variable used in "expression" are at different precision to a? The uncontroversial answer might be to adjust the result to the precision of a. But hold on... we have expression templates, and these can use variable a as working space while evaluating the expression... so the change in precision might occur *during* the computation and not after it. * Should we try to ban mixed precision arithmetic altogether? It's a tempting idea, but I can't see how to enforce it in code without also banning mixed precision assignment. Thanks for your consideration, John. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

2 1

[MSM] Still maintained?
by Deniz Bahadir 22 Aug '18

22 Aug '18

Hi Boost-list, because I realized that my simple PR for Boost.MSM [1] (which makes it compilable with C++17) and an even older one did not receive any attention, I wonder if Boost.MSM is still actively maintained. The latest changes seem to be from around December 2017. Does anyone know, if Christophe is still active? Best regards, Deniz [1] https://github.com/boostorg/msm/pull/15 -- BENOCS GmbH Dipl.-Inform. Deniz Bahadir Reuchlinstr. 10 D 10553 Berlin Germany Phone: +49 - 30 / 577 0004-22 Email: deniz.bahadir(a)benocs.com www.benocs.com Advisory Board (Chairman): Oliver Fietz Board of Management: Stephan Schröder, Dr.-Ing. Oliver Holschke, Dr.-Ing. Ingmar Poese Commercial Register: Amtsgericht Bonn HRB 19378

1 0

Increasing BOOST_PP_VARIADICS_SIZE
by Damien Buhl 20 Aug '18

20 Aug '18

Dear Edward, In comparison to BOOST_PP_SEQ, BOOST_PP_VARIADICS is limited to 64 elements while BOOST_PP_SEQ is limited 255. Is there a reason for the choice of 64 or could I patch BOOST_PP_VARIADICS to go as BOOST_PP_SEQ to a limit of 255 ? Or asked differently do you think there are in newer compilers/standards a way to have an unbounded BOOST_PP_VARIADICS implementation nowadays ? Warm Regards, -- Damien Buhl Software Developer +33 6 77 43 10 05

2 2

ABI issues with -std
by Peter Dimov 20 Aug '18

20 Aug '18

At some point, we'll need to acknowledge the problem which results from building Boost with one -std and user code with another, and deal with it somehow, if just by documenting. Most of our libraries don't suffer from it at the moment but Boost.System does, because of my changes; its ABI changes between 03/11/14. So I'm going to take the initial hit. :-) POSIX platforms have long been able to ignore ABI issues so we don't mangle the library names there at all, but now whether one builds Boost for C++03, C++11 or C++14 matters, and there's nothing to prevent linking C++xx to C++yy. Even with --layout=versioned, the cxxstd level is not encoded. The fact that the default C++ standard differs between g++ and clang++ doesn't help; when following the instructions of doing "b2 install", with g++6 and above you get C++14, but with g++5 or clang++ you get C++03. The latter is very rarely what one wants today.

7 26

Formal review request: Synapse
by Emil Dotchevski 16 Aug '18

16 Aug '18

Hello, I'm requesting a formal review for Synapse, a non-intrusive signal programming library. Synapse is a non-intrusive C++ signal programming library. It is able to register connections and emit signals from any C or C++ object of any type whatsoever. If two contexts share access to a C or C++ object, they can use that object as a randezvouz point of sorts, and communicate with each other through Synapse signals. A system of meta signals provides interoperability with other signal programming libraries and callback APIs. In particular Synapse can be used to safely register C++ function objects, including lambda functions, with any C-style callback API that is designed to work only with C function pointers. In a multi-thread environment signals can be emitted asynchronously and scheduled for synchronous execution when requested in other threads. There have been numerous improvements since the first review, including the the ability to create persistent connections which don't require the user to explicitly keep them alive. See https://zajo.github.io/boost-synapse/. Thanks, Emil

2 1

Strange libstdc++ versions in travis-ci testers
by Andrzej Krzemienski 15 Aug '18

15 Aug '18

Hi Everyone, Maybe someone could help me understand the configuration on the travis-ci testers. Whenever I push a new commit I get a number of failures from travis-ci about missing std::is_trivially_default_constructible from the standard library; like here: https://travis-ci.org/boostorg/optional/builds/397519342?utm_source=email&u… Some tests with Boost.Predef indicate that they are clang compiler 3.X, and clang 5 with libstdc++ of strange version nubers: macro BOOST_LIB_STD_GNU gives values 450400026 and 460700026, which would correspond to releases 2015-04-26 and 2016-07-26, but when I look at the release notes for GCC there are no releases mentioned of these dates: https://gcc.gnu.org/news.html Maybe someone knows what versions of libstdc++ these are? Or maybe I am missing something obvious? Regards, &rzej;

5 12

numeric directory/namespace
by Robert Ramey 14 Aug '18

14 Aug '18

I'm preparing to make adjustments to safe_numerics directory and namespace in preparation to incorporating safe_numerics into the official boost distributions. I have a couple of decisions to make that someone/everyone will want to weigh in on. There is already a directory boost_root/libs/numeric which seems to be an "umbrella" for libraries dealing with numerics. It includes conversion, interval, odeint and ublas. There is an index.html in there also. But instead of referring to the above libraries, it points to the ublas documentation. So it's sort of tempting the place safe numerics in libs as a sub directory. But I really have strong reservations about the whole concept of have this "umbrella" directory in the first place. Personally I'd just prefer to use boost_root/libs/safe_numerics. I don't think the extra structure adds anything and makes it harder to implement tools which scan the directories. It would also mean that I should ? use #include <boost/numeric/safe_numeric/ ....> and I'm not sure want to do that. Also I expect I'll want to sync the namespace boost::numeric::safe_numeric:: ... with the file system. It just seems more complex and flexible than it has to be. I see the future of boost as diminishing coupling between libraries and I see the current setup as not helping with this. Please don't wait to answer until I've made the changes. Robert Ramey

3 2

[container] [flat_map] Error with heterogeneous comparator and std::string_view
by Viktor Sehr 13 Aug '18

13 Aug '18

On MSVC (latest) the following code yields a compile error with flat_map, but not with std::map. I do not have the knowledge of std::less<> to resolve what causes the error. auto fm = boost::container::flat_map<std::string, int, std::less<> >{}; auto m = std::map<std::string, int, std::less<> >{}; auto k = std::string_view{ "my_key" }; auto x = m.find(k); // Compiles auto y = fm.find(k); // Does NOT compile Error message: 1>boost\container\flat_map.hpp(1314): error C2664: 'boost::container::vec_iterator<boost::container::dtl::pair<Key,T> *,true> boost::container::dtl::flat_tree<boost::container::dtl::pair<Key,T>,boost::container::dtl::select1st<Key>,Compare,boost::container::new_allocator<T2>>::find(const std::basic_string<char,std::char_traits<char>,std::allocator<char>> &) const': cannot convert argument 1 from 'const std::string_view' to 'const std::basic_string<char,std::char_traits<char>,std::allocator<char>> &' 1> with 1> [ 1> Key=std::string, 1> T=int, 1> Compare=std::less<void>, 1> T2=boost::container::dtl::pair<std::string,int> 1> ] 1> boost\container\flat_map.hpp(1314): note: Reason: cannot convert from 'const std::string_view' to 'const std::basic_string<char,std::char_traits<char>,std::allocator<char>>' 1> boost\container\flat_map.hpp(1314): note: No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called Best regards /Viktor

4 7

Library Federation
by Robert Ramey 12 Aug '18

12 Aug '18

I'm now taking steps to get safe numerics integrated into the boost distribution. It's reminded me of a running complaint I have about using boost. a) When I use anything boost, I'm required to do two things: i) run b2 headers to create a forwarding header in the boost directory ii) include via command line or INCLUDE variable to boost root. b) If I want to use safe_numerics before it is included in the boost distribution, I have to place safe_numerics into it's expected destination in the boost hierarchy and run b2 headers AGAIN to make things match up. This is even more problematic in that b2 headers is not invoked "automagically" in such a way that people don't know it's there. To me, this just makes it harder to use / test any new library with boost without dragging in access to a bunch of stuff I may not want. It inhibits those without beam foo from running the tests etc. This is why I did things the way I did. Now I'm getting ready to add it to the boost distribution, I'll change this to do it the "boost way". Not so much because I think it's better but in this case, consistency is better than variety. But I'm still unsatisfied with the situation. It's part of the reason that boost is avoided when possible by many people. Isn't there a better way? I think there might be. Rather than sprinkling a bunch of forwarding headers around my file system - which are "sticky" and need to be updated from time to time, how about depending on the "INCLUDE" environmental variables available in gcc and msvc and clang. Using "some method", I would be able generate this variable via some sort of batch script - not too tough. And work as I do now. But a) the script would be re-run when ever I changed projects so that it "stuck" in my file system. b) It could be smarter - include only the boost include directories I'm actually using - thus avoiding accidently including surprising stuff. c) We have tools which figure out boost dependencies automatically so I don't think it would be a big stretch to do this automagically. d) If my project is "larger" and includes a bunch of stuff from other libraries, I could add these in as well. This would give my the concept of "library federation" where my app is linked to some list defined as part of the project. I'm sure this concept also sort of exists. e) my pet request would be that I could say: tool application.cpp ... >include environment output to generate the env output for all the target apps. Of course one could you * wild cards as well. This would let me create one set on includes for building/running my test suite and a different one for examples and a different one for my "real" application. I'll stop there so as to leave opportunity for discussion. Robert Ramey

3 7

Please merge into boostorg superproject
by James E. King III 11 Aug '18

11 Aug '18

Please merge into boost superproject - these have passed CI and have been reviewed: https://github.com/boostorg/boost/pull/186 https://github.com/boostorg/boost/pull/181 Please decide what to do with: https://github.com/boostorg/boost/pull/39 (I can't tell if this is defunct?) https://github.com/boostorg/boost/pull/184 (do we want this in the superproject, or a submodule called boostorg/docker, or not at all?) Thanks, Jim

1 0

iostreams in 1.68.0
by James E. King III 11 Aug '18

11 Aug '18

Hi folks, just a note that none of the changes since 1.67.0 got into 1.68.0 master. They were on develop and never merged. I just merged them for 1.69.0. - Jim

1 0

[release] 1.69.0 open for merging
by Marshall Clow 10 Aug '18

10 Aug '18

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 Release schedule explanation: https://github.com/boostorg/boost/wiki/Release-Schedule Release practices for developers: http://svn.boost.org/trac/boost/wiki/ImprovingPractices -- The Boost Release Team

2 1

[release] Boost 1.68.0
by Marshall Clow 09 Aug '18

09 Aug '18

Release 1.68.0 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 libraryand numerous enhancements and bug fixes for existing libraries. For details, including download links, see <https://www.boost.org/users/news/version_1.68.0> You can also download directly from: <https://dl.bintray.com/boostorg/release/1.68.0/> To install this release on your system, see <https://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. Thanks, -- The Boost Release Team

5 5

Re: [boost] [Boost-users] [release] Boost 1.68.0 Beta 1 -> warnings in gil, locale, geometry, asio, ublas, interprocess, atomic
by Frédéric 09 Aug '18

09 Aug '18

Here are some more warnings while using the libraries: * gil: boost/gil/extension/toolbox/image_types/indexed_image.hpp:190:5: warning: les qualificatifs de type sont ignorés sur le type retourné par la fonction [-Wignored-qualifiers] const std::size_t num_colors() const { return _num_colors; } ^~~~~ boost/gil/extension/dynamic_image/any_image_view.hpp:41:63: warning: unused parameter 'v' [-Wunused-parameter] template <typename T> result_type operator()(const T& v) const { return num_channels<T>::value; } boost/gil/extension/dynamic_image/algorithm.hpp:147:70: warning: unused parameter 'src' [-Wunused-parameter] template <typename V, typename Value> static void apply(const V& src, const Value& val) { throw std::bad_cast();} ^ boost/gil/extension/dynamic_image/algorithm.hpp:147:88: warning: unused parameter 'val' [-Wunused-parameter] template <typename V, typename Value> static void apply(const V& src, const Value& val) { throw std::bad_cast();} ^ boost/gil/extension/dynamic_image/image_view_factory.hpp:178:140: warning: unused parameter 'cc' [-Wunused-parameter] typename color_converted_view_type<any_image_view<ViewTypes>, DstP, CC>::type color_converted_view(const any_image_view<ViewTypes>& src,CC cc) {~ ^ boost/gil/extension/dynamic_image/image_view_factory.hpp:201:144: warning: unused parameter 'cc' [-Wunused-parameter] typename color_converted_view_type<any_image_view<ViewTypes>, DstP, CC>::type any_color_converted_view(const any_image_view<ViewTypes>& src,CC cc) {~ ^ boost/gil/io/device.hpp:446:31: warning: unused parameter 'data' [-Wunused-parameter] void write( const byte_t* data ^ boost/gil/io/device.hpp:447:31: warning: unused parameter 'count' [-Wunused-parameter] , std::size_t count ) ^ boost/gil/io/device.hpp:471:35: warning: unused parameter 'data' [-Wunused-parameter] std::size_t read( byte_t* data ^ boost/gil/io/device.hpp:472:35: warning: unused parameter 'count' [-Wunused-parameter] , std::size_t count ) ^ * locale: boost/locale/utf.hpp:224:17: warning: cette instruction peut poursuivre son chemin [-Wimplicit-fallthrough=] c = (c << 6) | ( tmp & 0x3F); ^ boost/locale/utf.hpp:225:13: note: ici case 2: ^~~~ boost/locale/utf.hpp:231:17: warning: cette instruction peut poursuivre son chemin [-Wimplicit-fallthrough=] c = (c << 6) | ( tmp & 0x3F); ^ boost/locale/utf.hpp:232:13: note: ici case 1: ^~~~ * geometry: boost/geometry/formulas/vertex_longitude.hpp:340:32: warning: unused parameter 'lon1' [-Wunused-parameter] static inline CT apply(CT& lon1, ^ boost/geometry/formulas/vertex_longitude.hpp:341:32: warning: unused parameter 'lat1' [-Wunused-parameter] CT& lat1, ^ boost/geometry/formulas/vertex_longitude.hpp:343:32: warning: unused parameter 'lat2' [-Wunused-parameter] CT& lat2, ^ boost/geometry/formulas/vertex_longitude.hpp:344:38: warning: unused parameter 'vertex_lat' [-Wunused-parameter] CT const& vertex_lat, ^ boost/geometry/formulas/vertex_longitude.hpp:345:32: warning: unused parameter 'alp1' [-Wunused-parameter] CT& alp1, ^ boost/geometry/formulas/vertex_longitude.hpp:346:44: warning: unused parameter 'azimuth_strategy' [-Wunused-parameter] Strategy const& azimuth_strategy) ^ boost/geometry/strategies/spherical/intersection.hpp:544:81: warning: unused parameter 'b2' [-Wunused-parameter] Point2 const& b1, Point2 const& b2, // in ^ boost/geometry/algorithms/detail/envelope/segment.hpp:156:61: warning: unused parameter 'lon1' [-Wunused-parameter] static inline void compute_box_corners(CalculationType& lon1, ^ boost/geometry/algorithms/detail/envelope/segment.hpp:158:61: warning: unused parameter 'lon2' [-Wunused-parameter] CalculationType& lon2, ^ boost/geometry/strategies/spherical/intersection.hpp:544:81: warning: unused parameter 'b2' [-Wunused-parameter] Point2 const& b1, Point2 const& b2, // in ^ * asio (windows 32 and 64 bits with mingw w64 + g++ 8.2.0) : /softs/win32-mingw-8.2.0/release/boost/include/boost/asio/detail/impl/win_iocp_socket_service_base.ipp: Dans la fonction membre « boost::system::error_code boost::asio::detail::win_iocp_socket_service_base::cancel(boost::asio::> /softs/win32-mingw-8.2.0/release/boost/include/boost/asio/detail/impl/win_iocp_socket_service_base.ipp:253:51: warning: transtypage entre types de fonctions incompatibles de « FARPROC » {aka « int (__attribute__((stdcall)) *)()> cancel_io_ex_t cancel_io_ex = (cancel_io_ex_t)cancel_io_ex_ptr; ^~~~~~~~~~~~~~~~ * ublas: /softs/lin64-gcc-8.2.0/debug/boost/include/boost/numeric/ublas/matrix_expression.hpp:2224:17: warning: cette instruction « if » ne protège pas… [-Wmisleading-indentation] if (it2_ != it2_end_) ^~ /softs/lin64-gcc-8.2.0/debug/boost/include/boost/numeric/ublas/matrix_expression.hpp:2227:21: note: …cette instruction, mais l'indentation de cette dernière est trompeuse car elle fait croire qu'elle est gardée par le « if » if (it2_ != it2_end_) { ^~ boost/numeric/ublas/functional.hpp:1673:57: warning: unused parameter 'size_i' [-Wunused-parameter] size_type upper_element (size_type i, size_type size_i, size_type j, size_type size_j) { ^ boost/numeric/ublas/functional.hpp:1673:88: warning: unused parameter 'size_j' [-Wunused-parameter] size_type upper_element (size_type i, size_type size_i, size_type j, size_type size_j) { ^ * interprocess (windows mingw-w64 + g++ 8.2.0 32/64 bits): In file included from boost/interprocess/errors.hpp:41, from boost/interprocess/exceptions.hpp:24, from boost/interprocess/sync/file_lock.hpp:24, from Progs/delypse-transfer.cpp:32: boost/interprocess/detail/win32_api.hpp:189:8: warning: « struct boost::interprocess::winapi::IUnknown_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IUnknown_BIPC ^~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:200:8: warning: la classe de base « struct boost::interprocess::winapi::IUnknown_BIPC » a un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IWbemClassObject_BIPC : public IUnknown_BIPC ^~~~~~~~~~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:200:8: warning: « struct boost::interprocess::winapi::IWbemClassObject_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] boost/interprocess/detail/win32_api.hpp:306:8: warning: la classe de base « struct boost::interprocess::winapi::IUnknown_BIPC » a un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IWbemContext_BIPC : public IUnknown_BIPC ^~~~~~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:306:8: warning: « struct boost::interprocess::winapi::IWbemContext_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] boost/interprocess/detail/win32_api.hpp:345:8: warning: la classe de base « struct boost::interprocess::winapi::IUnknown_BIPC » a un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IEnumWbemClassObject_BIPC : public IUnknown_BIPC ^~~~~~~~~~~~~~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:345:8: warning: « struct boost::interprocess::winapi::IEnumWbemClassObject_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] boost/interprocess/detail/win32_api.hpp:369:8: warning: la classe de base « struct boost::interprocess::winapi::IUnknown_BIPC » a un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IWbemServices_BIPC : public IUnknown_BIPC ^~~~~~~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:369:8: warning: « struct boost::interprocess::winapi::IWbemServices_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] boost/interprocess/detail/win32_api.hpp:518:8: warning: la classe de base « struct boost::interprocess::winapi::IUnknown_BIPC » a un destructeur non virtuel accessible [-Wnon-virtual-dtor] struct IWbemLocator_BIPC : public IUnknown_BIPC ^~~~~~~~~~~~~~~~~ boost/interprocess/detail/win32_api.hpp:518:8: warning: « struct boost::interprocess::winapi::IWbemLocator_BIPC » a des fonctions virtuelles et un destructeur non virtuel accessible [-Wnon-virtual-dtor] In file included from boost/interprocess/errors.hpp:41, from boost/interprocess/exceptions.hpp:24, from boost/interprocess/sync/file_lock.hpp:24, from Progs/delypse-transfer.cpp:32: boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::get_system_time_of_day_information(boost::interprocess::winapi::system_timeofday_information&) »: boost/interprocess/detail/win32_api.hpp:1676:58: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> dll_func::get(dll_func::NtQuerySystemInformation); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::unlink_file(const char*) »: boost/interprocess/detail/win32_api.hpp:1892:78: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> (NtSetInformationFile_t)dll_func::get(dll_func::NtSetInformationFile); ^ boost/interprocess/detail/win32_api.hpp:1894:94: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> NtQueryObject_t pNtQueryObject = (NtQueryObject_t)dll_func::get(dll_func::NtQueryObject); ^ boost/interprocess/detail/win32_api.hpp:1966:85: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> NtOpenFile_t pNtOpenFile = (NtOpenFile_t)dll_func::get(dll_func::NtOpenFile); ^ boost/interprocess/detail/win32_api.hpp:1967:73: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> NtClose_t pNtClose = (NtClose_t)dll_func::get(dll_func::NtClose); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::get_file_mapping_size(void*, long long int&) »: boost/interprocess/detail/win32_api.hpp:2413:63: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> (NtQuerySection_t)dll_func::get(dll_func::NtQuerySection); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::get_semaphore_info(void*, long int&, long int&) »: boost/interprocess/detail/win32_api.hpp:2426:86: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> (winapi::NtQuerySemaphore_t)dll_func::get(winapi::dll_func::NtQuerySemaphore); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::query_timer_resolution(long unsigned int*, long unsigned int*, long unsigned int*) »: boost/interprocess/detail/win32_api.hpp:2437:98: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> (winapi::NtQueryTimerResolution_t)dll_func::get(winapi::dll_func::NtQueryTimerResolution); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::query_performance_counter(long long int*) »: boost/interprocess/detail/win32_api.hpp:2444:57: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> dll_func::get(dll_func::QueryPerformanceCounter); ^ boost/interprocess/detail/win32_api.hpp: Dans la fonction « bool boost::interprocess::winapi::query_performance_frequency(long long int*) »: boost/interprocess/detail/win32_api.hpp:2451:59: warning: transtypage entre types de fonctions incompatibles de « boost::interprocess::winapi::farproc_t » {aka « int (__attribute__((stdcall)) *)() »} vers « boost::interprocess:> dll_func::get(dll_func::QueryPerformanceFrequency); ^ * atomic (OSX): boost/include/boost/atomic/detail/ops_gcc_x86_dcas.hpp:269:113: warning: unused parameter 'order' [-Wunused-parameter] static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT

4 6

Note: the Master branch is not yet open for merging
by Marshall Clow 09 Aug '18

09 Aug '18

Even though we have a release, I've got some tagging to do, etc. The master branch will be open tomorrow. -- Marshall

1 0

[release] Boost 1.68.0 Release Candidate 1
by Marshall Clow 05 Aug '18

05 Aug '18

The release candidates for the 1.68.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.68.0/source/> The SHA256 checksums are as follows: 59804d8fad02cf3b09485f3dbc0f9097c05fc1e0123f0c133b35a6c6f601109a boost_1_68_0_rc1.7z 7f6130bc3cf65f56a618888ce9d5ea704fa10b462be126ad053e80e553d6d8b7 boost_1_68_0_rc1.tar.bz2 da3411ea45622579d419bfda66f45cd0f8c32a181d84adfa936f5688388995cf boost_1_68_0_rc1.tar.gz 3b1db0b67079266c40b98329d85916e910bbadfc3db3e860c049056788d4d5cd boost_1_68_0_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 web site will be updated today as well.

6 8

[release] Boost 1.68.0 Beta 1
by Marshall Clow 02 Aug '18

02 Aug '18

Boost release 1.67.0 beta 1 is now available at: https://dl.bintray.com/boostorg/beta/1.68.0.beta1/source/ The files are identical to the RC2 that was posted on Friday. 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 For details of what's in the release, see <http://www.boost.org/users/history/version_1_68_0.html>. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team

3 7

Moving wiki/Guidelines/WarningsGuidelines
by Mateusz Loskot 02 Aug '18

02 Aug '18

Hi, Paul Bristow suggested [1] "We might also re-host this document somewhere on github/boostorg?" [1] https://lists.boost.org/Archives/boost/2018/07/242617.php I'd like to edit and move the wiki page away from Trac. IMHO, it is reasonable to host it not on GitHub wiki but on boost.org along other guidelines, for example, at https://www.boost.org/development/warnings.html - It is easy to update website via pull requests. - Any updates would be a subject of some review at least Thoughts? Objections? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

3 7

[release] 1.68.0 closed for release
by Marshall Clow 02 Aug '18

02 Aug '18

The master branch is now closed for all changes except by permission. The commit-bot isn't running on master, so the super project will need to be manually updated for any changes. If all goes well, the release candidate should be out tomorrow. Thanks, -- The Boost Release Team

1 0

[release] 1.68.0 post-beta merges
by Marshall Clow 01 Aug '18

01 Aug '18

The master branch is is now open for post-beta merges, but only as described in the Post-Beta Merge Policy. See <https://github.com/boostorg/boost/wiki/Release-Beta-Merge-Policy> The master branch will close for the 1.68.0 release on August 1st. -- Marshall

11 34

[filesystem] PR backlog needs attention
by James E. King III 01 Aug '18

01 Aug '18

There are 29 open PRs going back 3 years. This backlog needs some attention. Some of the pull requests (like documentation changes to fix typos) are trivial. I ran into a warning while building another library that I found was already submitted as a fix in the PRs, but has missed the 1.68.0 release now. Thanks, Jim

4 5