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copied boost files in other projects
by Oliver Kowalke 12 Dec '16

12 Dec '16

I encountered some projects that have copied files from boost and replaced the copyright and license notice by their own. Other projects have added their own license (for isntance MIT, LGPL ...) beside the Boost license notice in the copied files - does this mean that the code is dual licensed now?. How does the boost community deal with this? Oliver

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Review period has ended for the Synapse library
by Edward Diener 12 Dec '16

12 Dec '16

The review period has officially ended for the Synapse library by Emil Dotchevski. I have received one e-mail specifying a review that will come sometime today and therefore will wait before making my decision as Review Manager for that review and Emil's possible response. I would like to thank all those who took part in the review during the review period, and Emil for responding to the remarks of those who have participated. I know another library will shortly begin its review, but I will not rush my final analysis and decision regarding Synapse and intend to make it sometime by the end of this week. Edward Diener, review manager

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Re: [boost] [synapse] Synapse library review starts today December 2
by Barrett Adair 12 Dec '16

12 Dec '16

On Fri, Dec 2, 2016 at 8:19 AM, Edward Diener <eldiener(a)tropicsoft.com> wrote: > - What is your evaluation of the design? I don't know anything about Signals2, but I find the "non-intrusive" argument to be compelling. I don't like that the invocation mechanism is single-threaded by default. I think the thread_local approach is interesting, but it sounds ripe for confusion in application code. > - What is your evaluation of the implementation? This code style is quite foreign to me, but it seems consistent. The mix of Boost and std libraries seems arbitrary (e.g. boost::shared_ptr and <thread>). The Boost.Function dependency appears redundant. The callback is effectively being erased twice. std::invoke or equivalent could serve as a replacement. I don't much like signal_traits.hpp and the limitations it imposes. Arity is capped at 4 parameters, and the signal type must be passed explicitly. The latter is surely good for compile times, but I think it would be nice to have a deduced signal type version that could still support stateful lambdas and member functions. I browsed the test cases, and they seem rather in-depth. I think some comments in this code are warranted. > - What is your evaluation of the documentation? The tutorial is very well done. Overall, the documentation is very solid. I enjoyed reading it. Quickbooks and syntax highlighting would be nice. This line was disappointing: "requires compiler support for the following C++11 features" I have seen this in existing Boost library documentation, so there is precedent, but I do not like it at all. I much prefer to see a range of tested compiler versions, even if it's only a couple. Continuous integration services like Travis and Appveyor are free, and very useful toward this end. > - What is your evaluation of the potential usefulness of the > library? It appears that it could be useful to Qt users. I personally would not find this useful. > - Did you try to use the library? With what compiler? Did you > have any problems? I ran the logger example with GCC 5.3 on Ubuntu 16.04. No problems. > - How much effort did you put into your evaluation? A glance? A > quick reading? In-depth study? 4 hours combined of reading the documentation and playing around with the implementation code. > - Are you knowledgeable about the problem domain? My experience with C++ signal libraries is limited. I am comfortable using the Intel TBB flow graph library, which has some degree of overlap. I have a bit of experience with event-driven programming in other languages. I am knowledgeable about C++ callable types and compiler support for their variations. > - Do you think the library should be accepted as a Boost library? This is my first formal review participation, I don't have a library in Boost, I'm not familiar with Signals2, and I do not have a use case for Synapse, so I'm not going to answer this question. Please consider this message as a "technical comment" instead. P.S. For whatever it's worth, I did fork the Synapse code and implement tentative variadic support in connect.hpp and emit.hpp (though I did not get around to translate.hpp). https://github.com/zajo/boost-synapse/compare/master...badair:master It appears to work as-is with the logger example, but similar work would need to be done in translate.hpp to make it fully variadic. I used my proposed CallableTraits library with the intention of implementing deduced signal types, but I ran out of willpower. Please forgive the aggressive formatting.

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Boost.IOStreams mapped_file_sink missing flush() functionality
by AB 11 Dec '16

11 Dec '16

Hello, I wish to bring to your attention two issues regarding mapped_file_sink from Boost.IOStreams (release 1.62.0): 1. There is no member function `mapped_file_sink::flush()` which I would like to use in my program. I believe it could be implemented portably by using `msync()` for POSIX and `FlushViewOfFile()` for Windows; was the omission of this function a deliberate choice or a minor oversight? 2. The member functions `begin()` and `end()` are implemented for mapped_file_sink but are not documented! This will lead to programmers relying strictly on the docs to use `data()` and `data()+size()` instead. Please update the documentation for the next release 1.63.0.

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[1.63.0] Master is closed for beta release + release notes
by Daniel James 10 Dec '16

10 Dec '16

Hello everyone, The master branch is now closed for the beta release. Please can you add any remaining entries to the release notes, either by emailing me, or by creating a pull request at: https://github.com/boostorg/website/blob/master/feed/history/boost_1_63_0.q… To do so, click on the little pencil icon at the top right of the code. thanks, Daniel

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Synapse library review final 2 days
by Edward Diener 10 Dec '16

10 Dec '16

Today and tomorrow are the last 2 days of the review of the Synapse library by Emil Dotchevski. If anybody intends to review the Synapse library but cannot finish their review this weekend, but will be able to finish their review by this coming Monday, please e-mail me and I will take into account your review when making my decision as Review Manager. I encourage all those who are interested in signal/slot programming to look at Synapse and make a review. Synapse is a signal programming library, similar to Boost Signals2 and the signals-slots system in Qt. The main difference is that Synapse is non-intrusive: the address of any object of any static type whatsoever can be passed to synapse::emit to emit a signal. This makes it possible to emit Synapse signals from objects of third-party types as well as system objects (e.g. standard FILE pointers, HWNDs, etc.) or any other object that can be converted to a pointer. The library has been formatted to fit the Boost directory and namespace structure. To get Synapse, clone 'https://github.com/zajo/boost-synapse.git' into a directory called 'synapse' under your boost/libs directory. See the tutorial at 'http://zajo.github.io/boost-synapse/Tutorial.html', or read full documentation at 'http://zajo.github.io/boost-synapse/index.html'. You can also view the documentation locally from your clone of the library at boost/libs/synapse/doc/index.html.

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[stacktrace] Prereminder of Boost.Stacktrace review starting 14th
by Niall Douglas 10 Dec '16

10 Dec '16

I know we are all likely feeling a bit of tired of reviewing potential new Boost libraries, but I just wanted to remind everyone that Antony's Stacktrace library will start its peer review this coming Wednesday Dec 14th with the review lasting until just before Christmas, Dec 23rd. I appreciate this reminder is a little early given the Synapse review doesn't finish until tomorrow, but today I have the time to do email using both hands, and I likely won't get the time again until next weekend (newborns force a lot of single handed typing with your neck twisted hard to the side. Very slow). Edward I hope this doesn't get in the way of concluding your very interesting review. Antony's Stacktrace library adds a long overdue facility to Boost, a formal portable API for obtaining and parsing the call stack of a thread of execution. It has three user selectable backends, tries to provide a maximum performance (nomalloc) stack capture and I think by now can serialise stacktraces to storage. I'll be honest in saying I sent a long list of fairly strong concerns I had with the design and implementation to Antony last month, but I'll defer in the review to whatever the community votes (increasingly me and the Boost consensus seem to be diverging on what makes for good design and practice). I'll make the formal review announcment on Wednesday, but for those wanting to get started early go to: Github: https://github.com/apolukhin/stacktrace Docs: http://apolukhin.github.io/stacktrace/index.html Regards, Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

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[fusion] Compilation errors on Intel compiler (C++14)
by Andrey Semashev 08 Dec '16

08 Dec '16

Hi, I'm seeing compilation errors coming from Boost.Fusion headers on Sandia-intel-17.0-c++14: http://www.boost.org/development/tests/develop/developer/output/Sandia-inte… Notably, the same tests compile fine in C++11 mode on the same compiler, which makes me think that is related to C++14 mode specifically. Looking at the code, it seems the compiler makes constexpr functions implicitly const-qualified even though it shouldn't in C++14 mode, so it's likely a compiler bug. Still, is it possible to add a workaround?

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Solaris Boost Install headaches
by Paluzzi, Aaron 08 Dec '16

08 Dec '16

Hello, I'm currently banging my head against a Boost install on Solaris 10 Sparc. I started with a 1.57 download and install. This had mild success using the "Getting started" documentation with some compilation errors. I've been asked to upgrade this to 1.62, and now I'm getting errors as follows when I run ./bootstrap.sh $ ./bootstrap.sh -n Building Boost.Build engine with toolset ... Failed to build Boost.Build build engine Consult 'bootstrap.log' for more details In the Bootstrap.log file I get the following: ./build.sh: syntax error at line 135: `machine=$' unexpected I've been unable to find any further documentation on this error. Any assistance would be appreciated. Actually an in depth install guide for Solaris would be appreciated. I've had no issues on Windows, but Solaris is giving me migraines.

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Synapse library review ongoing
by Edward Diener 07 Dec '16

07 Dec '16

We are in our final 5 days of the review of the Synapse library. We have had some good discussions about Synapse for those willing to review the library, but we really need much more from those who are, or might be, interested. Without wishing in any way to limit reviews or discussions to specific topics I would like to suggest to those interested in the library that they might address soem of these particular questions about Synapse in their commenst or review: 1) Is the documentation understandable for programming with Synapse ? 2) Does the library successfully achieve what it says it can do, providing a non-intrusive signal/slot system ? 3) Is the Synapse syntax easy enough for a programmer to use ? 4) Does testing show that Synapse works with user's code ? 5) Is the design of the library clear enough and flexible enough to make working with it viable ? While I realize that much of the discussion has been about particular end-user's preferences for a signal/slot library or Synapse's way of doing signal/slot programming versus Boost Signals/Signals2, all important topics in a review, it would be helpful if reviewers or commenters would consider Synapse for what it does do, even if they might not personally find a use for it in their programming tasks. ----------------------------------------------------------------------- Synapse is a signal programming library, similar to Boost Signals2 and the signals-slots system in Qt. The main difference is that Synapse is non-intrusive: the address of any object of any static type whatsoever can be passed to synapse::emit to emit a signal. This makes it possible to emit Synapse signals from objects of third-party types as well as system objects (e.g. standard FILE pointers, HWNDs, etc.) or any other object that can be converted to a pointer. The library has been formatted to fit the Boost directory and namespace structure. To get Synapse, clone 'https://github.com/zajo/boost-synapse.git' into a directory called 'synapse' under your boost/libs directory. See the tutorial at 'http://zajo.github.io/boost-synapse/Tutorial.html', or read full documentation at 'http://zajo.github.io/boost-synapse/index.html'. You can also view the documentation locally from your clone of the library at boost/libs/synapse/doc/index.html.

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Re: [boost] Asynchronous library now in Boost Library Incubator
by Christophe Henry 07 Dec '16

07 Dec '16

>boost.asynchronous looks to have many of the same features/functionality as HPX. >Can I ask why you chose to reimplement futures/lightweight thread pools/parallel STL/etc, >rather than working on improving HPX to suit your needs? I don't think the libraries have the same goals (or at least it seems to me so). Asynchronous is first of all an architecture tool focusing on organizing a whole application into thread worlds. The libraries also do not have the same design / tradeoffs. Asynchronous can make use of futures but encourages callbacks and tries to make these as safe as possible. The goal is to be as asynchronous (meaning non-blocking) as possible. It is no coincidence that I'm also the author of Boost.MSM. The encouraged design is a whole lot of state machines, each in its own thread (possibly sharing a thread), sending tasks to threadpools, TCP connections, etc. and waiting for callbacks. Future-based designs do not mix well with state machines' run-to-completion. The reason for the non-blocking focus is that I'm using the library at work in an industrial 24/7 application. When working on the production line, blocking is a disaster. If an algorithm goes astray, or simply takes longer than usually, blocking the production line results in huge costs. Crashes due to races also. Asynchronous provides ways to avoid both. >JB >Disclaimer : I have contributed o HPX, but I'm not one of the "German HPC Guys" :) . No hard feeling. I'm grateful for participation and the chance to explain the underlying ideas of the library. Thanks, Christophe

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[serialization][test] failures in serialization causing regressions
by Barend Gehrels 06 Dec '16

06 Dec '16

> The regression matrix in develop of Boost.Geometry contains many new > compilation failures due to: > > > 1) : D:\t08\run\boost_root\boost/serialization/array.hpp(25) : error C2039: 'array' : is not a member of 'std' > > 2): > ../boost/numeric/ublas/storage.hpp: In member function ???void boost::numeric::ublas::unbounded_array<T, ALLOC>::serialize(Archive&, unsigned int)???: > ../boost/numeric/ublas/storage.hpp:331:18: error: ???make_array??? is not a member of ???boost::serialization??? > ar & serialization::make_array(data_, s);and a > > > The master is still OK. > > Can this be solved? Ping! This is still the case! Robert, can you explain this? It is (of course) not only geometry failing, also ublas or (if there are) other libraries with ublas dependencies: http://www.boost.org/development/tests/develop/developer/numeric-ublas.html All yellow! Thanks, Barend

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Re: [boost] [process] Formal Review starts today, 27 October
by Bjorn Reese 04 Dec '16

04 Dec '16

On 10/27/2016 08:26 AM, Antony Polukhin wrote: > - Whether you believe the library should be accepted into Boost > * Conditions for acceptance I withhold judgement for now to give the author an opportunity to respond. At the moment I am unsure whether to vote for conditional acceptance or rejection. > - Your knowledge of the problem domain Advanced on Unix. > You are strongly encouraged to also provide additional information: > - What is your evaluation of the library's: > * Design I have a couple of serious concerns. My first concern is about the use of tagged arguments, and especially the redirection operators, in constructors. Instead I propose that the library uses the Named Parameter idiom (see [1], not to be confused with what Niall labelled "tagged name parameter" idiom.) The bp::child object should not execute in the constructor, but rather via operator(). That way we can use the named parameter idiom to build up redirections and similar modifications. For example: auto compile = bp::child("c++").output(bp::null); compile("main.cpp"); // Executes My second concern is about deadlocking. The FAQ shows two ways of deadlocking. I would expect the latter (the ls example) to work without further ado because that is how any newcomer would write their code. My third concern is about the chaining of pipes between processes. The tutorial shows an example where the output of the nm command is forwarded to the c++filt command. However, the forwarding is not done directly from the nm process to the c++filt process, but goes via the parent process. This can incur a performance degradation when nm generates much output. Is it possible to chain them directly? Besides "nm myfile | c++filt" that is. I also have the following minor comments / questions. Is it possible to redirect stderr to stdout? (like 2>&1). The reference documentation only mentions this under asynchronous pipe output. The bp::starting_dir should be renamed to bp::current_path to be consistent with Boost.Filesystem. Consider renaming bp::spawn to avoid confusion with boost::asio::spawn which is how you launch coroutines with Boost.Asio. I am missing a this_process::get_id() function to return the current process identifier. > * Implementation My major concern with the implementation is that the library is only header-only, so I cannot compile it as a static library if I wish to. There are several Boost header-only libraries that allows you to do that. The reason why I find this important for Boost.Process is because I want to avoid getting platform-specific C header files included into my project when I include a Boost.Process header. The library should throw its own process_error exception which inherits from system_error, similar to Boost.Filesystem. I did not investigate the implementation in greater detail. > * Documentation The documentation is lacking an entire chapter with an overall description of the library and the concepts used. For instance: * What are processes and pipes? * What are the possible invocation mechanisms? Some of this is mentioned in the Design Rationale, but that is not the place where developers seek their information. * How to set search paths or the current working directory. * How to use environment variables. * this_process Tutorial / Synchronous I/O: What is the default behaviour when I/O redirections are not specified? Tutorial / Asynchronous I/O: Consider including an example with boost::asio::spawn as a way to obtain the yield context. Reference / child: Does not mention how the life-time of the object and the child process are related. For instance, the documentation on the destructor only mentions that it is a destructor. Reference / cmd: bp::cmd will parse the input string as a sequence of space-separated arguments. Is it spaces or whitespaces? Is it possible to have escapes for arguments that do contain spaces? > * Tests Did not investigate. > * Usefulness A process library is a very useful addition to Boost. > - Did you attempt to use the library? If so: > * Which compiler(s) > * What was the experience? Any problems? Did not try. > - How much effort did you put into your evaluation of the review? About 4-5 hours (one of which was gratuitously donated by daylight saving time.) [1] https://en.wikibooks.org/wiki/More_C%2B%2B_Idioms/Named_Parameter

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API/ABI changes report for Boost
by Ponomarenko Andrey 02 Dec '16

02 Dec '16

Hello, The report on API/ABI changes in the latest releases of Boost: https://abi-laboratory.pro/tracker/timeline/boost/ The report is generated by the open-source abi-tracker tool and updated three times a week. Hope it will be helpful for users and maintainers of the library. Thank you.

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[poly_collection] Request for comments: fast polymorphic collections
by Joaquin M López Muñoz 02 Dec '16

02 Dec '16

A couple of years ago I wrote two blog entries about high-performance data structures for polymorphic objects: http://bannalia.blogspot.com/2014/05/fast-polymorphic-collections.html http://bannalia.blogspot.com/2014/05/fast-polymorphic-collections-with.html that spurred some interest in the community. Now I've had the time to turn these ideas into something resembling a full-fledged library: https://github.com/joaquintides/poly_collection http://rawgit.com/joaquintides/poly_collection/website/doc/html/index.html and I'd be very grateful if people could give their opinion on usefulness, design, etc. so as to determine potential interest in an eventual official submission to Boost. Thank you, Joaquín M López Muñoz

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Re: [boost] Asynchronous library now in Boost Library Incubator
by Christophe Henry 01 Dec '16

01 Dec '16

>After having a deeper dive into the documentation and examples, one >pattern I see popping up quite >frequently is this: >future<R> fut = my_promise.get_future(); >post_callback(some_work, [this](expected<R> r) { >this->my_promise.set_value(r.get()); }); >return fut; This is simply to make examples easier to run (it finishes the example). It demonstrates that the only one which blocks in an application built on Asynchronous is main(). This might be more confusing than useful and I probably should get rid of this. >Is there any performance/usability drawback from this (might have gotten >the syntax wrong here): >return post_future(pool, some_work); > >Why is the former to be preferred to the latter, or vice versa? post_future is the preferred for simple applications or examples. It is similar to std::async (without the problem of blocking futures and with different continuations). post_callback is the design the library seeks to promote for bigger applications: post a task to a threadpool, get a callback posted to the queue of the caller's thread world. >Regarding the documentation overall, >it seems to miss a proper reference section. >For example, boost::asynchronous::expected is used almost >everywhere, but not documented. My bad. Will be corrected. Thanks, Christophe

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Asynchronous library now in Boost Library Incubator
by Christophe Henry 01 Dec '16

01 Dec '16

Dear Community, The Asynchronous library is now listed in the Boost Library Incubator ( http://blincubator.com/bi_library/asynchronous-2/?gform_post_id=1654) I took a lot of time since first presenting it in C++ Now 2014 in order to extend the scope and intensively test the library. The library has been in use in production code for already 1.5 years, has survived billions of calls and usage 24/7, so its core is stable and quite tested. All algorithms have not been used though so that bugs are possible there. The reason for using the Incubator is, the library is quite big and 2 weeks review will not be sufficient so I hope for comments, discussions or pre-reviews earlier on. Asynchronous is first of all an architecture tool. It allows organizing a complete application into Thread Worlds, each world having the possibility to use the same or different threadpools for long-lasting tasks. The library provides an implementation of the Active Object pattern, extended to allow many Active Objects to live in the same World. It provides several Threadpools and many parallel algorithms making use of them. And most important of all, it allows simple, blocking-free asynchronous programming based on thread-safe callbacks. It also provides very useful logging and HTML diagnostics (see https://htmlpreview.github.io/?https://raw.githubusercontent.com/henry-ch/a…) to allow better understanding of code. I look forward to an interesting and lively discussion. Christophe

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Upcoming review of the Synapse library starting tomorrow
by Edward Diener 01 Dec '16

01 Dec '16

The formal review of the Synapse library by Emil Dotchevski starts tomorrow, December 2 and is scheduled to continue through December 11. I will be making an official announcement tomorrow, but I want to give the following information today for anyone wishing to acquaint themselves with the library. As explained previously by Emil Dotchevski when requesting that Synapse be put on the Boost Review list, Synapse is a signal programming library, similar to Boost Signals2 and the signals-slots system in Qt. The main difference is that Synapse is non-intrusive: the address of any object of any static type whatsoever can be passed to synapse::emit to emit a signal. This makes it possible to emit Synapse signals from objects of third-party types as well as system objects (e.g. standard FILE pointers, HWNDs, etc.) or any other object that can be converted to a pointer. The library has been formatted to fit the Boost directory and namespace structure. To get Synapse, clone 'https://github.com/zajo/boost-synapse.git' into a directory called 'synapse' under your boost/libs directory. See the tutorial at http://zajo.github.io/boost-synapse/Tutorial.html, or read full documentation at http://zajo.github.io/boost-synapse/index.html. The documentaion can also be viewed from the local clone at boost/libs/synapse/doc/index.html. I would urge anyone who may be interested in signal/slot processing in C++ to take a good look at the Synapse library. Edward Diener, review manager

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Re: [boost] Asynchronous library now in Boost Library Incubator
by Christophe Henry 01 Dec '16

01 Dec '16

>I'm trying to digest the docs for this monster work. > >One things that strikes me immediately is that the doc preparation >does not use code snippets, and so code is in boring old >black'n'white rather than colored syntax. >For me, that makes it significantly harder to read (and understand) the code examples. Ok, I'll see if I can improve this. >It also means that one doesn't have the assurance that 'What You See is What Compiles'. For most features, the doc provides a link to an example, which I regularly compile. >(I've also having trouble finding things in all the plentiful 'good stuff'. >But that's a common (and largely still unsolved) >problem with all documentation.) >Paul Please let me know what is the "good stuff" for you and I'll make it more visible. Cheers, Christophe

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[compute] Remove boost::chrono lib dependencie
by Viktor Sehr 01 Dec '16

01 Dec '16

Hi, Would it be possible to remove the dependency for boost/chrono is boost/compute/detail/duration.hpp. As it already supports std::chrono via a macro, couldn't the inclusion of boost/chrono.hpp be excluded? As it is now, boost compute is dependent on having libboost_chrono-vc140-mt-gd-1_62.lib built. /Viktor

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[release] Boost 1.63.0 Beta 1
by Marshall Clow 29 Nov '16

29 Nov '16

The first beta packages for 1.63.0 beta 1 are now available: <https://sourceforge.net/projects/boost/files/boost/1.63.0.beta.1/> The SHA256 checksums are as follows: 3dbc1bca10941710755c13a00b1ae56d2d37fe90bbadcf9746203194f9d33e3a boost_1_63_0.7z c8b986fd57e436fd88dbc70e51d3e21efa2be3bdf835fa499b2cf6c0a8cc2985 boost_1_63_0.tar.bz2 745d99e4be9c0f324ec7ba15b7d228fd780067f2e8aeae2f16660a4cf6e6a051 boost_1_63_0.tar.gz e66bd6e2f637148c314398b92bc1f3cbdc777ee282f9de7885697afad3d9c202 boost_1_63_0.zip As always, the release managers would appreciate it if you download the archive of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. Thanks! -- The release managers

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Re: [boost] Asynchronous library now in Boost Library Incubator
by Christophe Henry 29 Nov '16

29 Nov '16

Hi Vicente, >> In theory, the standard version would suffice, except for Thread. >> Boost.Thread provides interruption points, which the standard does not. >> With the standard version, I would not be able to offer task interruption. >Could you explain why task interruption is associated to thread >interruption? Ah already implementation details :) Tasks are executed in schedulers (uisually threadpools), which manage 1 to n threads. To interrupt a task from outside, the library interrupts the thread running the task. To be exact, the task will be interrupted the next interruption point in encounters. The thread executing the task does not terminate but instead recovers and pops the next task from its job queue. >> I rely for the other parts also on Boost because the standard version had >> bugs on earlier versions of compilers, and quite some projects are still >> stuck with gcc-4.9 or mingw. At some points, it seemed easier to maintain >> using Boost (which also happens to be faster than the standard, at least on >> my tests). >> >Whow, glad to hear Boost.Thread is working for you Henry. It is. I got no problem whatsoever. >I believe that Michael is however right. Boost libraries restricted to >C++11 should use the standard library as much as possible. Sure. At the moment I have no way around Boost.Thread though. If that changes, I'll probably want to switch to standard. The performance issue for the clock is not a huge one and by that time, the older compilers will hopefully have vanished. I could provide a macro to switch between boost / std. If one needn't interrupt tasks, the library would make no use of boost at all. >It would be great to have a specific C++11 (language and standard >library) version of your library. Well, if there is interest, why not? >Good luck with the review, >Vicente >P.S. I've in my todo's list implement thread interruption on top of the >standard as Anthony showed in his book, but I have no time to work on >this now. Oh, it would be great. This really is a fantastic feature. Thanks, Christophe

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Re: [boost] Asynchronous library now in Boost Library Incubator
by Christophe Henry 29 Nov '16

29 Nov '16

Hi Michael, >Thank you for submitting this library to the the incubator in >preparation for a review. I saw your presentation in 2014 >and I believe that this library solves a common problem. >My first question: I see that the library is listed as C++11 and also >has dependencies on Boost.System, Boost.Thread, Boost.Chrono, >and Boost.DateTime. Much of the functionality provided by those >Boost libraries is now part of the C++11 or C++14 standard. >Can you comment on the specific Boost dependencies >and if the standard versions would suffice? A good question which deserves a rationale, which I will add. In theory, the standard version would suffice, except for Thread. Boost.Thread provides interruption points, which the standard does not. With the standard version, I would not be able to offer task interruption. I rely for the other parts also on Boost because the standard version had bugs on earlier versions of compilers, and quite some projects are still stuck with gcc-4.9 or mingw. At some points, it seemed easier to maintain using Boost (which also happens to be faster than the standard, at least on my tests). HTH, Christophe

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[ssl] SSL handshake takes forever sometimes
by Shuchen He 28 Nov '16

28 Nov '16

Hi, I have an application written in boost with SSL. I noticed that when the client network is down for a while and come back again. The SSL handshake sometimes take forever. I tried to kill the client application and run it again, the problem still there. The only way to make it work again was to reboot my client device. I'm using boost 1.60 on the client side and 1.58 on the server side. The SSL handshake code was copied from Boost SSL server and client example I modified a bit to suit my application needs. Does anyone experience the similar issue? If so, can you please let me know how do you fix it? It would be much appropriated if you could help me out on this issue. Below is the SSL handshake code. chat_client(boost::asio::io_service& io_service, boost::asio::ssl::context& context, tcp::resolver::iterator endpoint_iterator) : io_service_(io_service), socket_(io_service, context) { filesize_=0; isfileopen_=false; socket_.set_verify_mode(boost::asio::ssl::verify_peer); socket_.set_verify_callback( boost::bind(&chat_client::verify_certificate, this, _1, _2)); boost::asio::async_connect(socket_.lowest_layer(), endpoint_iterator, boost::bind(&chat_client::handle_connect, this, boost::asio::placeholders::error)); } bool verify_certificate(bool preverified, boost::asio::ssl::verify_context& ctx) { char subject_name[256]; X509* cert = X509_STORE_CTX_get_current_cert(ctx.native_handle()); X509_NAME_oneline(X509_get_subject_name(cert), subject_name, 256); log_time(); fprintf(logfile,"%s: Verifying %s\n",logtime.c_str(), subject_name); return preverified; } void handle_connect(const boost::system::error_code& error) { if (!error) { socket_.async_handshake(boost::asio::ssl::stream_base::client, boost::bind(&chat_client::handle_handshake, this, boost::asio::placeholders::error)); } else { log_time(); fprintf(logfile, " %s Connect to server failed: %s\n ",logtime.c_str(), error.message().c_str()); fflush(logfile); delete this; } } void handle_handshake(const boost::system::error_code& error) { if (!error) { ssl_handshake_ok=1; do_read_header(); } else { log_time(); fprintf(logfile,"%s: Handshake failed:%s\n ",logtime.c_str(), error.message().c_str()); } }

1 0

[poly_collection] request for help at performance testing
by Joaquin M López Muñoz 28 Nov '16

28 Nov '16

Hi, Some days ago I published the first version of (candidate) Boost.PolyCollection at https://github.com/joaquintides/poly_collection Performance tests are available at http://rawgit.com/joaquintides/poly_collection/website/doc/html/poly_collec… but GCC and Clang were run in a Travis VM and the resulting figures are noisy and not sufficiently accurate. I'm looking for volunteers willing to run the performance suite in one or more of the following environments: * Recent GCC, 32 bit * Recent GCC, 64 bit * Recent Clang 32 bit * Recent Clang, 64 bit The full suite in one environment takes 1.5-2h to execute. If you're interested, please contact me privately (so that we don't pollute the mailing list) and I'll provide you with further instructions on how to do the testing. Thank you! Joaquín M López Muñoz

1 0

[iterator] Orbiting iterators
by Jeremy Murphy 27 Nov '16

27 Nov '16

Hi, just wondering what the mood in Boost.Iterator is for new features? At work we recently found use for an orbiting iterator, specifically a circular one, which effectively wraps at the start/end of a bounded range. (The domain is digital signal processing.) Implementation details aside, does this feature sound desirable to the library? I call it an "orbiting" iterator because it is a specific (and useful) case of the more general rho-shaped orbiting iterator. The theory behind it is in chapter 2 of Elements of Programming, which happens to be the free sample chapter available: http://elementsofprogramming.com/032163537X_Sample.pdf#page=6 Anyway, if there is interest, I'll make a pull request. Cheers. Jeremy

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Re: [boost] [beast] Separation between parse and generation and asio
by Vinnie Falco 24 Nov '16

24 Nov '16

On Wed, Nov 23, 2016 at 10:45 PM, Felipe Magno de Almeida <felipe.m.almeida(a)gmail.com> wrote: > I'm trying Beast with avr-gcc to see how much footprint it would take > on embedded applications. Thank you for your interest in Beast! > Unfortunately, stream_concepts uses asio > types, which requires asio include which requires network includes > which will obviously fail in most microcontrollers. > > Would it be possible to make parse and read implementation less > dependent on each other? I see what you mean. Yes, I believe I can do that - would you mind creating a new issue here? https://github.com/vinniefalco/Beast/issues Thanks!

1 0

[outcome] Requesting pre-review of Boost.Outcome tutorial
by Niall Douglas 24 Nov '16

24 Nov '16

Dear Boost, I am hoping to bring Boost.Outcome, a C++ 14 library providing a factory and family of policy driven lightweight monadic value-or-error transports, into the Boost peer review queue by March 2017 followed shortly thereafter by an ACCU talk in April if my talk proposal passes their programme committee. To that end, I've written an explanation and a sort of tutorial explaining the history and purpose of Outcome at https://ned14.github.io/boost.outcome/ and I'd greatly appreciate if people could tell me: 1. Does it make sense? 2. Do you think you could use Outcome in your own code after reading it? 3. Do you think you would want to use Outcome in your own code after reading it? 4. Are there any missing parts which are showstoppers? My thanks in advance. Be aware the install stuff described at the start doesn't work yet. The reference documentation is also quite patchy thanks to doxygen not understanding CRTP. All that stuff and a fair bit more remains to fix before it's ready to enter the Boost peer review queue. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

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[beast] Separation between parse and generation and asio
by Felipe Magno de Almeida 24 Nov '16

24 Nov '16

Hello, I'm trying Beast with avr-gcc to see how much footprint it would take on embedded applications. Unfortunately, stream_concepts uses asio types, which requires asio include which requires network includes which will obviously fail in most microcontrollers. Would it be possible to make parse and read implementation less dependent on each other? Boost.Spirit x3 works very well on microcontrollers. I'd expect a different type for messages which could actually receive iterator pairs for strings with Beast might give a very good option for HTTP/WS implementation on microcontrollers. Regards, -- Felipe Magno de Almeida

1 0

[sort] Parallel sorting sub-library mini-review conclusion
by Christophe Henry 22 Nov '16

22 Nov '16

> I would like to know the memory used and the best, >normal and worst case of the Asynchronous sorting algorithms. The sort versions are mergesort so they use double memory. The quicksort versions require no extra memory while partitioning. When they degrade after some partitioning iterations, they require the extra memory used by the underlying sort algorithm (spreadsort, std:sort, intro_sort, etc.). Thank you Francisco for this interesting library which I shamelessly used into my own ;-) It's probably a bit late but I vote for acceptance. Cheers, Christophe

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Re: [boost] [sort] Parallel sorting sub-library mini-review. Performance tests.
by Christophe Henry 22 Nov '16

22 Nov '16

>> >> OTOH the single-threaded ones are interesting, especially the stable_sort >> and intro_sort for cases where usage of spreadsort is not possible. >> >I challenge you to find a sorting problem where it isn't possible to use >spreadsort. string_sort can sort anything that std::sort can; > you just need to convert the sort key comparison sequence into a sequence of bytes > and feed string_sort the correct functors. That said, it may not be >efficient to sort some problems with string_sort, >and it'll probably be too much work to be worth the effort for many problems. This is what I meant. Sorry for the lack of precision. I'll add it to my performance tests, it might be an interesting variant as the algorithm is really fast. >> >> A short summary: >> >> 100000000 uint64_t elements already sorted: >> Boost parallel sort : 0.064965 secs >> >> Asynchronous parallel sort : 0.0167134 secs (same with other >> algorithms) >> >> Asynchronous provides a special optimization for this case. >> >If this optimization is practical to incorporate in Boost parallel sort, >it is a common case and your solution seems noticeably faster, >so I would like Francisco to consider it. That said, .06s isn't bad. Sure. >> >> I added this one: >> 100000000 uint64_t elements reverse sorted >> >> Boost parallel sort : 0.581381 secs >> >> Asynchronous parallel sort : 0.0478701 secs >> >> Asynchronous provides a special optimization for this case. >> I this the library should do it too. This one is pretty common and a >> popular DOS attack. >> > This optimization would be nice to have, if it's cheap. A parallel reverse is in O(n) so it's cheap compared to a sort. >> >> 100000000 uint64_t elements randomly filled >> >> Asynchronous parallel quickspreadsort: 0.587432 secs >> Asynchronous quick_intro_sort : 0.728393 secs >> >> This mixing of quicksort degrading into a spreadsort works here best. >I find this algorithm interesting; Frankly, there is nothing special. It's simply a parallel partition, which degrades into a "normal" parallel merge sort (in this case spreadsort) after a while. >have you considered using MSD radix-based sorting to break up the data > for the threads in parallel? >For example, take T threads, have each thread take 1/T of the data > and bucket it into N MSD-based buckets (just like Spreadsort), >where T < N <= ~2^11, then merge the equivalent buckets, >and as you merge them hand them off to another thread to sort. >This will probably divide better if you find the max and min before bucketing >using a parallel min/max search. I admit I didn't. But it sounds really interesting and I think I'll have a go at it. I'm not a sort expert though. I approached this from the parallel perspective. >> 10000000 strings randomly filled >> >> OMP parallel sort : 1.05803 secs >> Boost parallel sort : 0.933055 secs >> >> OMP parallel stable sort : 1.12269 secs >> Boost sample sort : 0.889216 secs >> Boost parallel stable sort : 1.56564 secs >> >> Asynchronous parallel quickspreadsort: 0.788856 secs >> Asynchronous quick_intro_sort : 0.893652 secs >> >> Asynchronous parallel stable sort : 1.23495 secs >> Asynchronous boost::stable sort : 1.21817 secs >> >> Similar results. >> >> >> Let's move on to big objects: >> >> 1562500 elements of size 512 randomly filled >> H E A V Y C O M P A R I S O N >> >> OMP parallel sort : 0.308923 secs >> Boost parallel sort : 0.342992 secs >> >> Asynchronous parallel_quicksort : 0.246709 secs >> Asynchronous quick_intro_sort : 0.269666 secs >> >> Both quicksorts are best, with a slight advantage to intro_sort. >> >> The light comparison is similar. >> >Do we have your permission to copy and/or adapt your quick_intro_sort >algorithm into the Boost.Sort library? Please feel free to copy whatever might be useful. The library has a Boost license as it's intended for inclusion in Boost.I also took the freedom of adding the single-thread versions of Fernando's algorithms as basis for my parallel versions. The algorithm is quite simple. It's the same as quick_spreadsort, a quicksort which degrades into Francisco's intro_sort after some iterations. I just found it interesting to add a wrapper to Francisco's algorithm for the mini-review. It was just a quick test (no time for cleverer algorithms) but I'm pretty satisfied with the result and I'll keep these versions. >How is the worst-case performance relative to Francisco's library? The sort versions have O(n log n) like any merge sort. The quicksort have O(n log n) to O(n^2) as expected from a quicksort. Cheers, Christophe

1 0

Re: [boost] [sort] Parallel sorting sub-library mini-review. Performance tests.
by Christophe Henry 22 Nov '16

22 Nov '16

Hi, > The threads are created only 1 time*. Have I missed something? I checked sample_sort and I saw several sets of calls to std::async which is likely to create and destroy threads several times. >*parallel_sort, sample_sort* : this algorithm is commonly accepted as the >fastest for the parallel stable sort. >The implementation is *notoriously faster than the provided by the GCC compiler* >( based on Open MP ) using less memory. TBB don?t >provide parallel stable sort, and only have an experimental code in their web pages Indeed, I found it highly interesting. Cheers, Christophe

1 0

[release] Boost 1.63.0 - fixes
by Oliver Kowalke 22 Nov '16

22 Nov '16

unfortunately beta 1 does not contain fixes from boost.context and boost.fiber. could you add the fixes to the 1.63 release, please? Oliver

3 4

[sort] Parallel sorting sub-library mini-review starts tomorrow, 11 November
by Steven Ross 22 Nov '16

22 Nov '16

Dear Boost community, The mini-review of Francisco Tapia's Parallel sorting library begins tomorrow November 11, and ends November 20th. The purpose of this review is to assess whether the sub-library is useful and up to Boost software standards. If the Boost community agrees on both, Francisco and I will integrate it into the existing Boost.sort library as a separate sub-library from Spreadsort. In doing so we'll integrate the documentation with the existing documentation for Boost.Sort, making it more consistent. If you review Francisco's library, please make sure you're using a compiler that supports C++11, and answer each of these questions: 1. Were you able to run it and see accurate and fast results? Please specify your compiler, OS, and processor type, and any problems (or slowdowns) encountered. 2. Would you use this library if accepted? Why or why not? 3. What is your evaluation of the design? 4. What is your evaluation of the implementation? 5. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? The library is here: https://github.com/fjtapia/sort_parallel This library provides both stable and unstable sorting algorithms, in single threaded and parallel versions. - All the algorithms have average and worst case runtime of O(NLogN). - These algorithms do not use any other library or utility. To compile and run these you will need a *C++11 compliant compiler.* - *This library is *include only, only requiring* the files in the boost/sort/parallel folder, with no external dependencies.* - The algorithms use a comparison object, in the same fashion as std::sort, defaulting to the std::less object, which uses the < operator internally for comparisons. - The algorithms are exception safe, meaning that the exceptions generated by the algorithms guarantee the integrity of the objects to sort, but not their relative order. If the exception is generated inside the objects (in the move or in the copy constructor) the results can be unpredictable. The library has a a new parallel_sort algorithm *( internally named Block Indirect)*, for processors connected with shared memory*,* invented for the library. This new algorithm combines the speed of algorithms like the GCC parallel sort (based on OpenMP), or the Microsoft parallel buffered sort, with the small memory consumption of algorithms like the TBB sort and the Microsoft parallel Sort. Results from running on an I7 5820 with 12 threads: GCC parallel_sort 1,25 secs 1560 MB TBB parallel_sort 1,64 secs 783 MB Boost parallel_sort 1,08 secs 786 MB In a separate repository (because it uses licence-restricted software like TBB and Microsoft parallel sort, and can’t be included in the Boost library), you can find all the code needed to run the benchmarks, the library code, the benchmark programs, and shell scripts to compile and run it on your machine in Linux and Windows. For the Linux benchmarks you will need to install TBB. (https://github.com/fjtapia/sort_parallel_benchmark) We look forward to your feedback!

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Re: [boost] [sort] Parallel sorting sub-library mini-review. Performance tests.
by Christophe Henry 22 Nov '16

22 Nov '16

Hi Boost Community, I did not manage yet to write a full review. One week is a bit short so a few more days will be necessary. I provide some performance tests first. To check the library performance, I pitted it against my own versions of a parallel mergesort and quicksort provided by the asynchronous library ( https://github.com/henry-ch/asynchronous) which is now ready for review, so we have a stable state for testing. I also added a parallel version inside the asynchronous library using Francisco's single-thread implementations to compare with his parallel ones. I tested on a i7-5960X. Due to time limits, I could not test on more interesting NUMA platforms (I did not get the reviewed library to compile for my KNC) so the tests do not pretend to have value outside the i7 architecture. I linked with tbb_malloc_proxy to limit memory influence. In a nutshell. I'm not a big fan of the parallel version of the algorithms. It seems to be based on std::async, so that a lot of threads are started and joined at every call. I would suggest using a threadpool. OTOH the single-threaded ones are interesting, especially the stable_sort and intro_sort for cases where usage of spreadsort is not possible. Cheers, Christophe A short summary: 100000000 uint64_t elements already sorted: OMP parallel sort : 0.390899 secs Boost parallel sort : 0.064965 secs OMP parallel stable sort : 1.06128 secs Boost sample sort : 0.0695357 secs Boost parallel stable sort : 0.0662401 secs Asynchronous parallel sort : 0.0167134 secs (same with other algorithms) Asynchronous provides a special optimization for this case. I added this one: 100000000 uint64_t elements reverse sorted OMP parallel sort : 0.317039 secs Boost parallel sort : 0.581381 secs OMP parallel stable sort : 1.06448 secs Boost sample sort : 0.524746 secs Boost parallel stable sort : 0.73036 secs Asynchronous parallel sort : 0.0478701 secs Asynchronous provides a special optimization for this case. I this the library should do it too. This one is pretty common and a popular DOS attack. 100000000 uint64_t elements randomly filled OMP parallel sort : 1.03594 secs Boost parallel sort : 0.796447 secs OMP parallel stable sort : 1.28601 secs Boost sample sort : 0.818954 secs Boost parallel stable sort : 1.13604 secs Asynchronous parallel quickspreadsort: 0.587432 secs Asynchronous quick_intro_sort : 0.728393 secs This mixing of quicksort degrading into a spreadsort works here best. The parallel adaptation of intro_sort is not bad either and best of other library algorithms. Asynchronous parallel stable sort : 1.26141 secs Asynchronous boost::stable sort : 0.804814 secs Interesting. The stable version of the library easily beats std::stable_sort I used until now. 10000000 strings randomly filled OMP parallel sort : 1.05803 secs Boost parallel sort : 0.933055 secs OMP parallel stable sort : 1.12269 secs Boost sample sort : 0.889216 secs Boost parallel stable sort : 1.56564 secs Asynchronous parallel quickspreadsort: 0.788856 secs Asynchronous quick_intro_sort : 0.893652 secs Asynchronous parallel stable sort : 1.23495 secs Asynchronous boost::stable sort : 1.21817 secs Similar results. Let's move on to big objects: 1562500 elements of size 512 randomly filled H E A V Y C O M P A R I S O N OMP parallel sort : 0.308923 secs Boost parallel sort : 0.342992 secs Asynchronous parallel_quicksort : 0.246709 secs Asynchronous quick_intro_sort : 0.269666 secs Both quicksorts are best, with a slight advantage to intro_sort. The light comparison is similar. My test code (the modified benchmark.cpp provided by the library): https://github.com/henry-ch/asynchronous/blob/master/libs/asynchronous/test… The full test results: https://github.com/henry-ch/asynchronous/blob/master/libs/asynchronous/test…

3 2

[process] daemon ideas
by Dracon Pern 21 Nov '16

21 Nov '16

I am not sure if [process] is the right library, but I am thinking about building something to manage daemon install/uninstall across platforms, for example Windows's service, OS X's launchd, systemd, and SysV init. Every operating system offers some way to launch a daemon at boot, and also the ability to stop, recover, etc. The issue is they all do it slightly differently, unlike having a common main(). My thinking is to provide a thin layer for install/remove and service notification. I have looked at Boost.Application, but it's lacking install/uninstall, and also seems overly complicated. Thoughts? Thanks, -Eric

4 3

Re: [boost] [iterator] Orbiting iterators
by Jeremy Murphy 20 Nov '16

20 Nov '16

Hi Steve, On 21 Nov 2016 3:01 AM, "Steve M. Robbins" <steve(a)sumost.ca> wrote: > > On Sunday, November 20, 2016 8:25:20 PM CST Jeremy Murphy wrote: > > Hi, > > > > just wondering what the mood in Boost.Iterator is for new features? At work > > we recently found use for an orbiting iterator, specifically a circular > > one, which effectively wraps at the start/end of a bounded range. (The > > domain is digital signal processing.) > > That sounds like what CGAL calls a Circulator; c.f. http://doc.cgal.org/ > latest/Circulator/classCirculator.html Right, yeah. Unfortunately I can't view the documentation properly on my phone so I'll take a look later, but I imagine the principle is the same although the interface is not. > > Implementation details aside, does this feature sound desirable to the > > library? > > I've found these handy when iterating through graph edges incident on a > vertex, when you need to start on a specific edge. It's been ages since I've > used them so I can't recall the exact use case. Makes me wonder whether > something like this already exists in boost graph. As you pointed out with CGAL, domain-specific implementations do exist. Boost.Geometry has something too. I guess I'm interested in whether this need for circular iteration can be abstracted back to the plain old iterator. Cheers. Jeremy

1 0

[outcome] Requesting pre-review of Boost.Outcome tutorial
by Matus Chochlik 20 Nov '16

20 Nov '16

On Fri, Nov 11, 2016 at 8:27 PM, Niall Douglas <s_sourceforge(a)nedprod.com> wrote: > Dear Boost, > > I am hoping to bring Boost.Outcome, a C++ 14 library providing a > factory and family of policy driven lightweight monadic > value-or-error transports, into the Boost peer review queue by March > 2017 followed shortly thereafter by an ACCU talk in April if my talk > proposal passes their programme committee. To that end, I've written > an explanation and a sort of tutorial explaining the history and > purpose of Outcome at https://ned14.github.io/boost.outcome/ and I'd > greatly appreciate if people could tell me: > > 1. Does it make sense? > Yes, the explanation is useful and does make sense. > > 2. Do you think you could use Outcome in your own code after reading > it? > > 3. Do you think you would want to use Outcome in your own code after > reading it? > I'm already using something similar in my oglplus2 OpenGL wrapper and some other projects and I really like the technique. IMO the C++ community would benefit from having something like this in Boost. In my implementation the outcome is a pair of the "real" result and an "error info" which can be more elaborate than an error code + a policy which by default throws an exception from the error info when the outcome is destroyed. The function caller can explicitly cancel the throwing and just examine the error information. All functions returning outcome can be noexcept. > > 4. Are there any missing parts which are showstoppers? > I didn't try to use your implementation, but I don't see anything obvious. But a shorter initial tutorial would be helpful. > > > My thanks in advance. Be aware the install stuff described at the > start doesn't work yet. The reference documentation is also quite > patchy thanks to doxygen not understanding CRTP. All that stuff and a > fair bit more remains to fix before it's ready to enter the Boost > peer review queue. > BR, Matus

2 1

Info on Sprout libraries (related to Boost?)
by charleyb123 . 19 Nov '16

19 Nov '16

Looking at the (very impressive) Sprout libraries that distributes using the Boost license: Welcome to the Sprout C++ Libraries <http://bolero-murakami.github.io/Sprout/docs/index.html#welcome-to-the-spro…> C++11 constexpr based Containers, Algorithms, Random numbers, Parsing, Ray tracing, Synthesizer, and others. https://github.com/bolero-MURAKAMI/Sprout ...It appears to be actively maintained, and very interesting. Anybody know the background and roadmap on these libraries (they are not in Boost now, right?) I'm particularly interesting in more 'constexpr' and compile-time libraries showing up, where C++14 (and C++17) wholly "throws-open-the-door" on what you can do at compile time (for example, see the C++14 constexpr used as a full C compiler: https://github.com/kw-udon/constexpr-8cc ) Crazy stuff. --charley

3 2

[fiber] maintenance status
by Tatsuyuki Ishi 18 Nov '16

18 Nov '16

The fiber library seems to be still updated, but I can't get into the author to do a feature proposal or request a refactor. Please take a look at this: https://github.com/boostorg/fiber/issues/89 I have pinged Oliver 3 times, and also sent some emails to his git committer addresses (he uses two identities). If you (the maintainer) are aware of this issue, please respond; I'm willing to do code contributions, but I must have some opinions about that before I get on to the work.

2 1

BOOST_NO_CXX11_HDR_CODECVT confusion
by Robert Ramey 17 Nov '16

17 Nov '16

I use BOOST_NO_CXX11_HDR_CODECVT from config.hpp in order to selectively enable code which uses the built-in codecvt facets as opposed to the boost "home brew" one we've been using for a long time. I do similar things with other macros such as BOOST_NO_CXX11_HDR_FORWARD_LIST. Problems arise when I use a recent compiler such as gcc 6.2 with the switch -std=c++03 as in "/hpc-6.2/usr/local/bin/g++" -ftemplate-depth-128 -std=c++03 -O0 -fno-inline -Wall -g -dynamic -gdwarf-2 -fexceptions -fPIC -arch x86_64 -Wno-unused-variable -Wno-long-long -ftemplate-depth-255 -DBOOST_ALL_NO_LIB=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_LIB_DIAGNOSTIC=1 -DBOOST_SERIALIZATION_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_WSERIALIZATION_DYN_LINK=1 -I"../../.." -c -o "../../../bin.v2/libs/serialization/test/test_iterators.test/darwin-6.2~03/debug/test_iterators.o" "test_iterators.cpp" In this ease I would expect to find that BOOST_NO_CXX11_HDR_CODECVT is defined as C++ standard does not include <codecvt> headers for versions prior to C++ 11. But the test matrix http://www.boost.org/development/tests/develop/developer/output/Sandia-gcc-… for this compilers shows that BOOST_NO_CXX11_HDR_CODECVT is NOT defined when no -std=c++03 is used. OK - I see that for gcc 6.2 the default is C++ 14 if no switch is used. So the test matrix is OK. I'm not sure what the column is meant to test as it does specify a particular version as the other columns do. So I think the test for gcc 6.2 - and all the g++/clang compiler would be improved by specifying which version of the C++ standard they are actually testing. But I still have a problem. When I use the swithc -std=c++03 I expect that BOOST_NO_CXX11_HDR_CODECVT be defined as C++ versions prior to C++ 11 don't have header <codecvt>. Same goes for other headers required only for more recent compilers. But my expectations aren't realized as BOOST_NO_CXX11_HDR_CODECVT is not defined in this case. The leads to selection of library code which invokes an #error saying that it's not supported. Perhaps definition of BOOST_NO_CXX11_HDR_CODECVT is conditioned solely on the existence of <codecvt> rather than the existence of <codecvt> and the compiler running in C++ 11+ "mode". I think this is what is messing things up for me. I might be able to work around this if I config.hpp included a macro which indicated which standard version it's intended to support. It doesn't have this. But I wouldn't need it if the BOOST_NO... worked as I would expect. Robert Ramey

3 3

MSVC opensource deployment.
by Robert Ramey 16 Nov '16

16 Nov '16

This just showed up in my junk mail box. Vcpkg updates: Static linking is now available https://github.com/Microsoft/vcpkg With 90+ libraries in its catalog, Vcpkg makes it easier to find the right open source library for Visual C++ 2015. The latest update now supports static linking. This kind of interesting: a) Does this constitute and open-source source code deployment system that perhaps we might learn from/exploit? b) I'm intrigued with the comment under "License": "Code licensed under MIT License" Boost is in this repository - I don't remember changing the Boost license. Robert Ramey

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[Sort] Parallel Sorting Mini review ends November 20th (Need reviewers)
by Francisco José Tapia 16 Nov '16

16 Nov '16

Dear Boost community, The mini-review of Francisco Tapia's Parallel sorting library began in November 11, and ends November 20th. The purpose of this review is to assess whether the sub-library is useful and up to Boost software standards. If the Boost community agrees on both, Francisco and I will integrate it into the existing Boost.sort library as a separate sub-library from Spreadsort. In doing so we'll integrate the documentation with the existing documentation for Boost.Sort, making it more consistent. If you review Francisco's library, please make sure you're using a compiler that supports C++11, and answer each of these questions: 1. Were you able to run it and see accurate and fast results? Please specify your compiler, OS, and processor type, and any problems (or slowdowns) encountered. 2. Would you use this library if accepted? Why or why not? 3. What is your evaluation of the design? 4. What is your evaluation of the implementation? 5. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? The library is here: https://github.com/fjtapia/sort_parallel This library provides both stable and unstable sorting algorithms, in single threaded and parallel versions. - All the algorithms have average and worst case runtime of* O(NLogN).* - These algorithms *do not use any other library or utility*. To compile and run these you will need a *C++11 compliant compiler.* - This library is *include only*, only requiring the files in the boost/sort/parallel folder, with no external dependencies. - The algorithms *use a comparison object*, in the same fashion as std::sort, defaulting to the std::less object, which uses the < operator internally for comparisons. - The algorithms are *exception safe*, meaning that the exceptions generated by the algorithms guarantee the integrity of the objects to sort, but not their relative order. If the exception is generated inside the objects (in the move or in the copy constructor) the results can be unpredictable. The library has a a* new parallel_sort algorithm ( internally named Block Indirect)*, for processors connected with shared memory, *invented for the library*. This new algorithm combines the speed of algorithms like the GCC parallel sort (based on OpenMP), or the Microsoft parallel buffered sort, with the small memory consumption of algorithms like the TBB sort and the Microsoft parallel Sort. Results from running on an I7 5820 with 12 threads: - GCC parallel_sort 1,25 secs 1560 MB - TBB parallel_sort 1,64 secs 783 MB - Boost parallel_sort 1,08 secs 786 MB In a *separate repository* (because it uses licence-restricted software like TBB and Microsoft parallel sort, and can’t be included in the Boost library), you can find *all the code needed to run the benchmarks*, the library code, the benchmark programs, and shell scripts to compile and run it on your machine in Linux and Windows. For the Linux benchmarks you will need to install TBB. (https://github.com/fjtapia/sort_parallel_benchmark) We look forward to your feedback!

1 0

[MPL] A Proposal
by Bruno Dutra 16 Nov '16

16 Nov '16

Dear Community, About a year ago today, there was a proliferation of threads [1][2][3] in this mailing list concerning the future of Boost.MPL, or even whether it had a future at all, and opinions diverged widely on the matter. Many have expressed concerns about the fact Boost.MPL was long outdated and proposed major changes to open path for modernization, while some others argued against it, fearing unexpected and disastrous side-effects could propagate throughout the rest of Boost. A few questioned if it was worth it at all to spend any further resources on Boost.MPL given the fact new alternatives were coming up, such as Boost.Hana, which departed entirely from template metaprogramming, yet some argued TMP remained a competitive alternative for type computations in C++14 as it has been demonstrated by Peter Dimov in his impressive articles [4] on modern TMP. Amidst all this, a proposal by Robert Ramey [5] caught my attention and inspired me to develop what I call Metal [6], a template metaprogramming library designed on the same core principles as Boost.MPL, but written from the very beginning to take full advantage of C++11. Metal was not designed to be a strict drop in replacement for Boost.MPL though, it was rather meant to be regarded as a modern version of Boost.MPL's original API, diverging only where it could really benefit from modern C++ and that essentially means gains of several orders of magnitude in performance** and lower memory consumption. At this point Metal is very close to where I originally intended to bring it and I think it's time I gauge interest from the community on a modest proposal I've been maturing along the past year. As a modern approach to the same task that Boost.MPL was meant to address, I don't believe Boost would benefit at all from yet another TMP library that would essentially compete with Boost.MPL and even Boost.Hana in some cases, specially as maintainers of older code that depends on Boost.MPL would have to go through major refactoring efforts in order to benefit from such an addition to Boost. I would like to propose something different instead. My proposal is to make Metal officially into a new revision of Boost.MPL's API, essentially MPL2 as the original proposal by Robert Ramey put it, merging both into one single TMP library. The idea would be to provide a thin proxy for the current Boost.MPL API which would have two backends configurable by preprocessor switches: the original implementation and a another one based on Metal. This way older code using Boost.MPL could see immediate gains on performance by selecting the newer backend on supported compilers, while at the same time legacy code maintained on older compilers could still rely on Boost.MPL's impressive ability to run virtually anywhere. On the other hand, newer projects interested on pure type computations would have the newer API entirely available to them. This proposal also overcomes the problem of dealing with the maintainability of Boost.MPL, since it provides a way for smooth transition from legacy hacks required by ancient compilers into a cleaner and easier to maintain C++11 codebase, besides avoiding any breaking changes within existing code in the process. Furthermore, should this proposal make it into Boost, I would be naturally willing to take responsibility for the maintenance of Boost.MPL, which AFAIK has been maintained by the CMT for quite some time now, often with limited resources. Comparing Metal and Boost.MPL there are a few noteworthy differences. Metafunction Classes have proven themselves entirely unnecessary and have thus been removed altogether in favour of pure Lambdas (in the Boost.MPL sense). Moreover, iterators make little sense in a functional world, so these too have been removed despite the fact they may easily be emulated in the new design. Moreover Metal develops the concept of optionals, that is, its metafunctions only have a nested ::type defined when they may be successfully computed, what may be safely tested using metal::is_just and may also be used to SFINAE out of miscomputations. Finally I'd like to point out that Metal was designed to be portable across as many compilers as possible and three of the most popular ones are continuously tested using Travis and Appveyor: Clang 3.5+, GCC 4.8+ and MSVC 14 (2015). I hope this is a reasonable proposal and I look forward into your opinions about it. ** Even though I haven't published any benchmarks yet, an example follows just to back my claims regarding performance (just tested on my personal laptop running linux): //Generate a list containing 10 thousand instances of std::integral_constant, from 0 to 9999 using l = metal::enumerate_t<metal::integer<10000>>; // GCC 5.3 ~0.4 s // Clang 3.7 ~0.5 s //Transform a list containing 5 thousand numbers by squaring each element using l1 = metal::enumerate_t<metal::number<long long, 5000>>; using l2 = metal::transform_t<metal::pow<metal::_1, metal::integer<2>>, l1>; // GCC 5.3 ~5.6 s // Clang 3.7 ~3.0 s [1]: http://thread.gmane.org/gmane.comp.lib.boost.devel/257680 [2]: http://thread.gmane.org/gmane.comp.lib.boost.devel/257983 [3]: http://thread.gmane.org/gmane.comp.lib.boost.devel/258843 [4]: http://pdimov.com/cpp2/simple_cxx11_metaprogramming.html [5]: http://rrsd.com/blincubator.com/bi_suggestion/mpl-lite-or-mpl2/ [6]: http://brunocodutra.github.io/metal/ Regards, Bruno Dutra

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Re: [boost] [MPL] A Proposal
by Bruno Dutra 16 Nov '16

16 Nov '16

On Nov 15, 2016 23:57, "Peter Dimov" <lists(a)pdimov.com> wrote: > > Bruno Dutra wrote: > >> Meanwhile, following Rene's suggestion to move away from Travis' container based infrastructure, I was also able to run tests on Clang 3.9 and even on what seems to be nightly snapshots of Clang 4.0: >> >> https://github.com/brunocodutra/metal/blob/develop/.travis.yml. > > > I don't care that much for 3.9 and 4.0, but the -stdlib=libc++ option is intriguing. Does it require sudo? I just checked and libc++-dev is whitelisted on Precise images, so it shouldn't require sudo. That said, the version of libc++ available on such an old version of Ubuntu might not fit your needs (it didn't mine) so you might need to upgrade to Trusty, in which case I believe it requires sudo, because it doesn't seem to be whitelisted yet.

1 0

[fiber] destruction order fiasco
by Tatsuyuki Ishi 15 Nov '16

15 Nov '16

The fiber still makes use of the scheduling algorithm after main context exits, which is a problem for my case that puts a stack-allocated shared data to the algorithm. Some points: https://github.com/boostorg/fiber/blob/master/src/context.cpp#L52 I doubt if the schwarz counter is needed; isn't it only one? https://github.com/boostorg/fiber/blob/master/src/scheduler.cpp#L137 I don't think there's a need to wake it up; if it's sleeping, the thread is blocked and it never enters here. This is the main problem: use-after-free. Anyway, what I think is ideal is that just making the algorithm a reference and assign it from the main context. An example of this approach is Qt's Q*Application.

1 0

Re: [boost] [Boost-users] [process] Formal review results
by Bjorn Reese 13 Nov '16

13 Nov '16

On 11/09/2016 07:45 PM, Antony Polukhin wrote: > The Boost.Process library is accepted. Unconditionally? Please notice that some of the votes were conditional, and if those conditions are not met, they should be counted as no votes. > The most controversial part of the library is it's interface. Many > comments were addressing: > * passing arguments > * starting process right in `system(...)` function The comments were about starting the process in the child constructor.

4 3

Boost.Config for clang on Linux with libc++
by Belcourt, Kenneth 13 Nov '16

13 Nov '16

Hi, Attached are user.hpp and the console output from running configure with clang-3.9. Note that I tried to configure using libc++ but the configure script immediately failed, so these are the results for clang-3.9 with the default stdlib (libstdc++). Can someone please take a look and see what adjustments might need to be made to Boost.Config to support this configuration? Once it works for the default stdlib, I’d like to rerun it to use libc++. Thanks, Noel Belcourt

3 4

[process] Formal Review
by Nat Goodspeed 13 Nov '16

13 Nov '16

I would like to surface a number of issues, large and small. You are clearly proud to support a number of different syntactic ways to express the same semantic operation. To me this is a minor negative. While in theory it sounds nice to be able to write Process consumer code any way I want, in a production environment I spend more time reading and maintaining other people's code than I do writing brand-new code. Since each person contributing code to our (large) code base will select his/her own preferred Process style, I will be repeatedly confused as I encounter each new usage. I admire the support for synchronous pipe I/O, while remaining skeptical of its practical utility. Synchronous I/O with a child process presents many legitimate opportunities for deadlock: traps for the unwary. I would be content with a combination of: * async I/O on pipes (yes, using Asio) * system() for truly simple calls * something analogous to Python's subprocess.Popen.communicate(): pass an optional string for the child's stdin, retrieve a string (or, say, a stringstream) for each of its stdout and stderr. The example under I/O pipes the stdout from 'nm' to the stdin of 'c++filt'. But the example code seems completely unaware that c++filt could be delayed for any of a number of reasons. It assumes that as soon as nm terminates, c++filt must have produced all the output it ever will. I worry about the Process implementation being confused about such issues. I'm dubious about the native_environment / environment dichotomy. As others have questioned, why isn't 'environment' a typedef for a map<string, string> (or unordered_map)? I understand that you desire to avoid copying the native process environment into such a map until necessary, but to me that suggests something like an environment_view (analogous to string_view) that can perform read-only operations on either back-end implementation. Operations involving splitting and joining on ':' or ';' should be defined purely in terms of strings and ranges of strings. They should not be conflated with environment-map support. The documentation so consistently uses literal ';' as the PATH separator that I worry the code won't correctly process standard Posix PATH strings. At this moment in history, an example showing integration of Process with Boost.Fiber seems as important as examples involving coroutines. Why is the native_handle_t typedef in the boost::this_process namespace? While in full context it makes sense to speak of "assigning" an individual process to a process group, the method name assign() has conventional connotations. Use add() instead. There's a Note that says: "If a default-constructed group is used before being used in a process launch, the behaviour is undefined." I assume you mean "destroyed before being used," but this is a concern. If a program has already instantiated a process group, but for any reason decides not to (or fails to) launch any more child processes, does that put the entire parent process at risk? What remedial action can it take? Move the group object to the heap somewhere and let it leak? Spawn a bogus child process for the purpose of defusing the ticking process group instance? If you're going to reify process group at all, you should wrap more logic around it to give it well-defined cross-platform behavior. And it should definitely be legal to create and destroy one without associating any child process with it. Given support elsewhere for splitting/joining PATH strings, the string_type path parameter to search_path() feels oddly low-level. Maybe accept a range of strings? > At a minimum, kindly state: > - Whether you believe the library should be accepted into Boost > * Conditions for acceptance YES, IF the present Boost.Process preserves the ability of its predecessor to extend it without modifying it. I'm sorry, thorough reading of the documentation plus some browsing through the code leaves me doubtful. Examples of such extensions: * With Boost.Process 0.5 I can use Boost.TypeErasure to pass an "initializer" which is a runtime collection of other initializers. Such a feature in Process 0.6 would support people's requests to be able to assemble an arbitrary configuration with conditional elements and use it repeatedly. * I can create an initializer (actually one for each of Posix and Windows, presenting the same API, so portable code can use either transparently) to implicitly forcibly terminate the child process being launched when the parent process eventually terminates in whatever way. Please understand that I am not asking for the above features to be absorbed into the Process library: I am asking for a Process library extensible enough that I can implement such things with consumer code, without having to modify the library. Perhaps Process 0.6 already is! It's just hard for me tell. Another feature should, in my opinion, be incorporated into the library: * On Windows, if you desire to pass any file handles at all to the new child process, it is completely whimsical what *other* open file handles you may inadvertently pass -- unless you play games with STARTUPINFOEXA and PROC_THREAD_ATTRIBUTE_LIST to enumerate exactly the set of handles you intend to pass. If the library doesn't natively support that, I *must* be able to pass a custom initializer with deep access to the relevant control blocks to set it up. This is a showstopper, as in "you can't remove that file because, unbeknownst to you, some other process has it open." > - Your knowledge of the problem domain I have hand-written process-management code in C++ several times before -- each with multiple implementations to support multiple platforms. I have tested the previous candidate Boost.Process 0.5 with a number of programs exercising a number of features. > You are strongly encouraged to also provide additional information: > - What is your evaluation of the library's: > * Design Design notes are at the top of this mail. > * Implementation I have only glanced over parts of the implementation. It seems somewhat more obscure than the corresponding pieces of Process 0.5, which is why I couldn't quickly satisfy myself as to the library's extensibility. > * Documentation Others have noted that the documentation is very sketchy in places. I too wish for more explanation. Much of the time I spent on this review was reading through the documentation. Apologies if I have misunderstood the library's capabilities. > * Usefulness I have felt for years now that it is essential to get a child-process management library into Boost. It grieves me to have to write platform-specific API calls into different applications. > - Did you attempt to use the library? I did not, sorry, ran out of time -- as you can infer from this review arriving at the end of the final day! > - How much effort did you put into your evaluation of the review? Most of my time was spent reading the documentation. I looked through a couple of the implementation files for further information.

4 8

Visual Studio 2015 Update 3 has removed std::unary_function and std::binary_function
by Marshall Clow 12 Nov '16

12 Nov '16

... if you build with /std:c++latest. See https://svn.boost.org/trac/boost/ticket/12586 for an example. Other vendors will be removing these types in C++17 mode in the future (or at least requiring a -D RETAIN_REMOVED_STUFF=1 or something like that) A quick grep for these terms found 153 instances of "std::unary_function" and 118 of "std::binary_function" across several libraries, including accumulators, algorithm, config, container, function, gil, graph, icl, mpi, msm, polygon, ptr_container, serialization, smart_ptr, tr1, unordered, utility - and probably others. I think that we ought to have a boost-wide solution for this (i.e, everyone should solve this the same way). I can think of three possibilities: * Deny, deny, deny: Boost doesn't work with C++17. Not my recommendation. * Since std::unary|binary_function is an empty struct with a set of two (or three) typedefs, just define the typedefs everywhere. Note that the typedefs (result_type, first_argument_type, second_argument_type) were deemed to not be useful in C++17 due to the existence of advanced type traits, etc. * Define a boost:unary_function and boost::binary_function struct that mimics the one that was in namespace std, and change over to use that. * Something else. Comments? -- Marshall

15 74

Adding any_dynamic_cast?
by Peter Dimov 12 Nov '16

12 Nov '16

I stumbled across https://github.com/bytemaster/Boost.DynamicAny which implements, in a fully backward compatible manner, dynamic cast functionality for boost::any. That is, it can give you X* from an 'any' holding a value of type Y if Y derives from X. It achieves this by simply changing template<typename ValueType> class holder : public placeholder { ValueType held; to template<typename ValueType> class holder : public placeholder, public ValueType which then enables dynamic_cast from holder<>* to OtherValueType*. This is pretty cool, and I don't remember seeing this idea anywhere else. Perhaps we should adopt it? One might even argue that this is how any_cast should always have worked, but I suppose we can't change it now for compatibility reasons. Although it's an interesting question whether C++17 'any' shouldn't be enhanced in this manner.

2 2

Request for a new submodule, tools/depinst
by Peter Dimov 12 Nov '16

12 Nov '16

I'd like to request the creation of a new submodule, tools/depinst, that will contain a Python script depinst.py which would, given a module in libs/, install the dependencies needed for running that module's tests. Currently, the .travis.yml files I use enumerate the dependencies manually, which is a bit tiresome: https://github.com/boostorg/function/blob/develop/.travis.yml - git submodule init libs/algorithm - git submodule init libs/align ... - git submodule init libs/type_traits - git submodule init libs/typeof - git submodule init libs/utility - git submodule init libs/winapi - git submodule init tools/build - git submodule update --depth 1 This will be replaced by just - git submodule update --init --depth 1 tools/depinst - git submodule update --init --depth 1 tools/build - python tools/depinst/depinst.py function

5 19

[CI] Activation for Boost.Units
by Jürgen Hunold 11 Nov '16

11 Nov '16

Hi Rene, could you please activate CI via Travis CI and Appveyor for Boost.Units? I hope that I have successfully adapted the scripts from Boost.Predef and that they work for Units as well. Is there any way to get myself some admin rights so I can scheduled cron jobs on TravisCI? I'd like to have at least a weekly run in order to check that no other library break units. And I noticed that the scripts don't work for my fork on GitHub. It needs to detect that and add a remote to the submodule in the Boost checkout somehow. Do you have any plans for that? Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! * voice: ++49 4257 300 ! Fährstraße 1 * fax : ++49 4257 300 ! 31609 Balge/Sebbenhausen * jhunold(a)gmx.eu ! Germany

2 1

[Beast] std::to_string not available in gcc 4.8?
by Vinnie Falco 11 Nov '16

11 Nov '16

A user is complaining that std::to_string is not available in their distribution. Beast doesn't support toolchains that don't have full support for C++11. However, if this is the only thing missing maybe I can just use a Boost equivalent to get him up and running. I see boost::to_string in <boost/exception/to_string.hpp> is that a public interface? It doesn't look documented. What do folks typically do when they want to call std::to_string on an unsupported distribution?

4 4

libs/regex/build/Jamfile.v2 missing "import testing"
by Peter Dimov 10 Nov '16

10 Nov '16

In a partial installation (not all submodules installed), running b2 in the Boost root says: libs\regex\build\Jamfile.v2:93: in modules.load ERROR: rule "unit-test" unknown in module "Jamfile<D:\tmp2\boost-root\libs\regex\build>". because libs/regex/build/Jamfile.v2 uses the unit-test rule, defined in testing.jam, but does not have "import testing ;". Adding that line fixes it. I've no idea why it works in a full installation - probably because someone else imports testing first before it gets to regex.

2 1

[process] Formal review results
by Antony Polukhin 09 Nov '16

09 Nov '16

The Boost.Process library is accepted. Congratulations to Klemens, and thanks to everybody who reviewed the library! The votes were as follows: + Johannes - Niall Douglas +/- Tom Kent +/- Nat Goodspeed + Paul A. Bristow +/- Bjorn Reese + Edward Diener + Boris Schäling +/- Raphaël Londeix + Klaim - Joël Lamotte Legend: + accept - decline +/- accept conditionally Separate thanks to Gavin Lambert for providing a solution to deadlocking problem. Additional thanks to Nat Goodspeed, Niall Douglas, Gavin Lambert, Raphaël Londeix and Bjorn Reese for spending significant amount of time on discussing, reviewing or testing the library. -- Quick review summary -- During the review multiple technical issues were raised and as far as I know, Klemens already working on them. The biggest win of the review - is a fix for possible deadlock with pipes. The most controversial part of the library is it's interface. Many comments were addressing: * passing arguments * starting process right in `system(...)` function Current approaches have benefits and drawbacks, other approaches have different benefits and drawbacks. At this point some people agree that the current approach is the lesser evil. Reviewers also wished to have better/richer documentation. P.S.: Please continue with the discussion and report issues that would help to improve the library. -- Best regards, Antony Polukhin

3 3

[dll] trouble building boost dll with Intel compiler on Windows
by Blower, Melanie 09 Nov '16

09 Nov '16

Hello, We are having trouble building boost_dll version 1.61 with Intel compiler (version 17.0) on Windows with vs2015 (and other versions of visual studio). There's a problem because the macro configuration causes alias.hpp to use gnu-like syntax to specify section names: we don't support this syntax in our Windows compiler. Instead, we support "#pragma section" just like the Microsoft compiler. Alias.hpp would use the "correct" configuration for our Windows compiler "#if BOOST_COMP_MSVC" (reference the file boost/dll/alias.hpp) However, the file boost/predef/compiler/visualc.hpp sets BOOST_COMP_MSVC to BOOST_VERSION_NUMBER_ZERO which is 0 I propose that alias.hpp could use BOOST_COMP_MSVC_BUILD instead of BOOST_COMP_MSVC. Does that seem reasonable? Thanks and regards, Melanie Blower (I work for Intel on the Intel C++ compiler)

5 11

[fusion] trouble building boost fusion with Intel compiler on Windows and Linux
by Blower, Melanie 09 Nov '16

09 Nov '16

Hello, We are having trouble building boost_fusion version 1.61 with Intel compiler (version 17.0) on Linux, and on Windows with vs2015 (and other versions of visual studio). The problem can be fixed if I made this change to boost/fusion/container/vector/detail/config.hpp : // Sometimes, MSVC 12 shows compile error with std::size_t of template parameter . #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1800)) \ || BOOST_INTEL /* add this line */ # if defined(BOOST_FUSION_HAS_VARIADIC_VECTOR) # undef BOOST_FUSION_HAS_VARIADIC_VECTOR # endif #endif Symptom on Windows: ile ..\..\..\bin.v2\libs\fusion\test\fold.test\cc848a939769f1f7cf08091b8a228ddb\algorithm\fold.obj.rsp "algorithm\fold.cpp" -Fo"..\..\..\bin.v2\libs\fusion\test\fold.test\cc848a939769f1f7cf08091b8a228ddb\algorithm\fold.obj" -TP /Z7 /Od /Ob0 /W3 /GR /MDd /Zc:forScope /Zc:wchar_t /nologo /Qwn5 /Qwd985 -Qoption,c,--arg_dep_lookup /Qvc14 -Qpchi- /wd4675 /EHs -c -DBOOST_ALL_NO_LIB=1 "-I..\..\.." compile-c-c++ ..\..\..\bin.v2\libs\fusion\test\fold.test\cc848a939769f1f7cf08091b8a228ddb\algorithm\fold.obj icl @"..\..\..\bin.v2\libs\fusion\test\fold.test\cc848a939769f1f7cf08091b8a228ddb\algorithm\fold.obj.rsp" fold.cpp ../../../boost/fusion/container/vector/vector.hpp(71): error: namespace "boost::fusion::vector_detail::result_of" has no member "value_at_c" : boost::is_convertible<Sequence, typename result_of::value_at_c<This, 0>::type> ^ detected during: instantiation of class "boost::fusion::vector_detail::is_convertible_to_first<Sequence, This, <unnamed>> [with Sequence=int, This=boost::fusion::vector<int>, <unnamed>=1]" at line 305 instantiation of "boost::fusion::vector<T...>::vector(U &&...) [with T=<int>, U=<int>]" at line 159 of "algorithm\fold.cpp" Symptom on Linux: The original failure on Linux (zip.test in boost_fusion) "icpc" -c -xc++ -O0 -g -w1 -inline-level=0 -fPIC -m64 -DBOOST_ALL_NO_LIB=1 -I"../../.." -c -o "../../../bin.v2/libs/fusion/test/zip.test/intl-lnx/dbg/algorithm/zip.o" "algorithm/zip.cpp" ../../../boost/fusion/container/vector/vector.hpp(230): error: pack "U" does not have the same number of elements as "I" : store<I, T>(std::forward<U>(var))... ^ detected during: instantiation of "boost::fusion::vector_detail::vector_data<boost::fusion::detail::index_sequence<I...>, T...>::vector_data(boost::fusion::vector_detail::each_elem, U &&...) [with I=<0UL, 1UL>, T=<boost::fusion::vector_iterator<const boost::fusion::vector<int, int>, 0>, boost::fusion::vector_iterator<const boost::fusion::vector<char, char>, 0>>, U=<const boost::fusion::transform_view<const boost::fusion::vector<const boost::fusion::vector<int, int> &, const boost::fusion::vector<char, char> &>, boost::fusion::detail::poly_begin, boost::fusion::void_> &>]" at line 306 instantiation of "boost::fusion::vector<T...>::vector(U &&...) [with T=<boost::fusion::vector_iterator<const boost::fusion::vector<int, int>, 0>, boost::fusion::vector_iterator<const boost::fusion::vector<char, char>, 0>>, U=<const boost::fusion::transform_view<const boost::fusion::vector<const boost::fusion::vector<int, int> &, const boost::fusion::vector<char, char> &>, boost::fusion::detail::poly_begin, boost::fusion::void_> &>]" at line 41 of "../../../boost/fusion/view/zip_view/zip_view_iterator.hpp" Thanks and regards, Melanie Blower (I work for Intel on the Intel C++ compiler)

3 4

test: Initializiation of data test cases
by Florian Lindner 09 Nov '16

09 Nov '16

Hello, I would like to use data test cases. The problem that comes with that, is that I want to use objects that needs the application to be initialized before they are instantiated. Example is that an object that uses MPI needs to habe MPI_Init called before. This example code shows the order in which different hooks are run: #define BOOST_TEST_DYN_LINK // #define BOOST_TEST_MAIN #include <boost/test/unit_test.hpp> #include <boost/test/data/test_case.hpp> #include <boost/test/data/monomorphic.hpp> #include <mpi.h> #include <iostream> #include <string> #include <vector> using namespace std; struct GlobalFixture { GlobalFixture() { cout << "GlobalFixture" << endl; } ~GlobalFixture() { } }; BOOST_GLOBAL_FIXTURE(GlobalFixture); struct Test : public std::string { // derive from string to get operator<< that boost requires Test() { cout << "Object to test" << endl; } }; namespace bdata = boost::unit_test::data; template <class T> class RuntimeDataset { public: using sample = typename T::value_type;; enum { arity = 1 }; T data; explicit RuntimeDataset(T _data) { cout << "Dataset constructor" << endl; data = _data; } bdata::size_t size() const { return data.size(); } typename T::const_iterator begin() const { return data.cbegin(); } }; namespace boost { namespace unit_test { namespace data { namespace monomorphic { template <class T> struct is_dataset<RuntimeDataset<T>> : boost::mpl::true_ {}; }}}} struct Fixture { Fixture() { cout << "Fixture" << endl; } }; BOOST_AUTO_TEST_SUITE(MySuite) BOOST_DATA_TEST_CASE_F( Fixture, test1, RuntimeDataset<std::vector<Test>>( { Test() } ), // This should be evaluated when the test is about to run input) { BOOST_TEST(true); cout << "Data test case" << endl; } BOOST_AUTO_TEST_SUITE_END() // initialization function: bool init_unit_test() { cout << "init_unit_test" << endl; return true; } // entry point: int main(int argc, char* argv[]) { cout << "main" << endl; int retCode = boost::unit_test::unit_test_main( &init_unit_test, argc, argv ); return retCode; } I've removed some code parts, but it should compile right away using mpic++ -std=c++11 -lboost_unit_test_framework boosttesting.cpp Its output is Object to test Dataset constructor main init_unit_test GlobalFixture Running 1 test case... Fixture Data test case *** No errors detected So, before I have any chance to do my own initialization code, the Test object and the dataset is constructed. I have posted this to the user mailing list, but still looking for a way to work around that. Do you have any idea how I can do initialization before data is instantiated? Thanks, Florian

1 0

cross-compiling linux->osx: file was built for archive which is not the architecture being linked (x86_64)
by Frédéric Bron 09 Nov '16

09 Nov '16

I am trying to cross-compile for osx from linux using clang. When I build boost, I use the following: CC="x86_64-apple-darwin13-clang" CFLAGS="-O2 -DNDEBUG" CXX="x86_64-apple-darwin13-clang++-libc++" CXXFLAGS="-O2 -DNDEBUG -std=c++14" AR="x86_64-apple-darwin13-ar" AS="x86_64-apple-darwin13-as" RANLIB="x86_64-apple-darwin13-ranlib" ./bootstrap.sh --without-icu --prefix=/softs/usr/darwin13-clang/release/boost --with-toolset=clang Then I use the following user-config.jam: using clang : : x86_64-apple-darwin13-clang++-libc++ : <cxxflags>-std=c++14 ; with the following command: ./b2 -d2 -j8 --layout=system --user-config=user-config.jam --without-mpi --without-python --without-context --without-coroutine link=static threading=multi runtime-link=shared target-os=darwin threadapi=pthread address-model=64 define=BOOST_THREAD_USE_LIB define=BOOST_LOG_WITHOUT_EVENT_LOG variant=release install Apart from a few errors, everythings looks fine: ...failed updating 3 targets... ...skipped 3 targets... ...updated 13684 targets... However, when I link against the static libraries that have been built, I get this type of messages: ld: warning: ignoring file /softs/usr/darwin13-clang/release/boost/lib/libboost_system.a, file was built for archive which is not the architecture being linked (x86_64): /softs/usr/darwin13-clang/release/boost/lib/libboost_system.a I suspect that it is because the wrong ar and ranlib where used because I find in my log that b2 used "ar" and "ranlib" instead of "x86_64-apple-darwin13-ar" and "x86_64-apple-darwin13-ranlib". So I changed my user-config.jam to: using clang : : x86_64-apple-darwin13-clang++-libc++ : <cxxflags>-std=c++14 <archiver>x86_64-apple-darwin13-ar <ranlib>x86_64-apple-darwin13-ranlib ; but b2 is still using "ar" and "ranlib". Any idea of what my problem is? Frédéric

1 1

Support for fixed point arithmetic in Boost?
by Juan Dent 08 Nov '16

08 Nov '16

Hi, Sorry if this is a dumb question but I have been looking for fixed point types in Boost and not found any... Yet I feel there must be... Thanks for any help Juan

4 5

Fw: Build failed: smart_ptr 1.0.31-develop
by Peter Dimov 08 Nov '16

08 Nov '16

I'm getting a weird error from the CI: https://ci.appveyor.com/project/pdimov/smart-ptr/build/1.0.31-develop C:/projects/boost-root/tools/build/src\build-system.jam:982: in load *** argument error * rule boostcpp.post-build ( ok ? ) * called with: ( ok ok ) * extra argument ok C:/projects/boost-root\boostcpp.jam:513:see definition of rule 'boostcpp.post-build' being called C:\projects\boost-root\tools\build\src/kernel\modules.jam:295: in import C:\projects\boost-root\tools\build\src/kernel/bootstrap.jam:139: in boost-build C:\projects\boost-root\boost-build.jam:17: in module scope Command exited with code 1 This is Submodule path 'tools/build': checked out '32113ca3ddbc637d08e85c44502f3149d37323e0'

2 1

[process] The Formal review preiod is nearing the end
by Antony Polukhin 07 Nov '16

07 Nov '16

Dear Boost community, The formal review of Klemens David Morgenstern's Process library ends on 5th November. If you're willing to write a review - please hurry up! If you're willing to write the review but could not make it on time - please give a hint. In that case it is possible to postpone the final decision for a few days. Thanks in advance! -- Best regards, Antony Polukhin

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[process] Formal review has ended
by Antony Polukhin 07 Nov '16

07 Nov '16

The library review has ended. I will need a few more days to calculate the votes and to wait for some people that spend a lot of time to make their vote more explicit. At this point, following people voted: * Johannes * Niall Douglas * Tom Kent * Paul A. Bristow * Bjorn Reese * Edward Diener * Boris Schäling If I've missed someone, please notify me. -- Best regards, Antony Polukhin

2 2

[iostreams] Last develop commit breaks release builds.
by Rene Rivera 07 Nov '16

07 Nov '16

FYI.. This commit: < https://github.com/boostorg/iostreams/commit/0a87de8932641a3896f49872a3c034… > Is causing release build errors. See the CI logs for details.. <https://circleci.com/gh/boostorg/boost/2190> Please address ASAP. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 2

[config] std::shuffle support
by Edward Diener 07 Nov '16

07 Nov '16

Does Boost config currently have a macro to determine whether the c++11 std::shuffle algorithm is supported for a particular compiler ? If not supporting /std:c++latest by changing std::random_shuffle to std::shuffle will not be possible for c++03 libraries.

3 6

interest in structure of arrays container?
by Michael Marcin 06 Nov '16

06 Nov '16

Structure of arrays is a pretty well known pattern for improving memory density and enabling vectorization in high performance code. Also known as parallel arrays[1]. After hand-rolling yet another of these it occurred to me that you make a reasonable first implementation with a simple alias template. template< typename... Ts > using soa = std::tuple< std::vector<Ts>... >; example: soa<int,float,std::string> data; This is decent start but has several issues including: * nothing to preserve the invariant keeping the arrays the same length * missing coalesced interface for vector methods (size, reserve, etc) * no iterator * wasted storage for duplicated allocators, capacities, sizes * sizeof...(Ts) allocations could be a single large block The work required to address these issues is not too great I think. Potential names: soa<Ts> structure_of_arrays<Ts> parallel_array<Ts> struct_array<Ts> parallel_vector<Ts> struct_vector<Ts> Does this already exist somewhere? Does it seem useful? [1]https://en.wikipedia.org/wiki/Parallel_array

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Re: [boost] [process] Formal Review starts today, 27 October
by Bjorn Reese 06 Nov '16

06 Nov '16

On 10/30/2016 02:21 PM, Bjorn Reese wrote: > On 10/27/2016 08:26 AM, Antony Polukhin wrote: > >> - Whether you believe the library should be accepted into Boost >> * Conditions for acceptance > > I withhold judgement for now to give the author an opportunity to > respond. At the moment I am unsure whether to vote for conditional > acceptance or rejection. I vote for conditional acceptance, provided the following conditions are met: 1. The interface style must be redesigned such that: a. There is a clear separation between arguments and attributes. b. Arguments and attributes should not be arbitrarily interspersed in the parameter list. c. A set of attributes can be build in advance, and reused for different child processes. d. Attributes can be optionally to the attribute-set. 2. There should be no I/O deadlocks by default. 3. An Overview section that introduces the concepts and the various parts of the library must be added to the documentation.

1 0

[process] Formal Review starts today, 27 October
by Antony Polukhin 05 Nov '16

05 Nov '16

Dear Boost community, The formal review of Klemens David Morgenstern's Process library begins today, 27th October and ends on 5th November. Process is a C++11 library to manage system processes. It can be used to: * create child processes * setup streams for child processes * communicate with child processes through streams (synchronously or asynchronously) * wait for processes to exit (synchronously or asynchronously) * terminate processes Full documentation with examples and tutorial is available at http://klemens-morgenstern.github.io/process/index.html Stable source codes for review are available at https://github.com/klemens-morgenstern/boost-process/tree/boost_review Latest source codes available at https://github.com/klemens-morgenstern/boost-process We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your knowledge of the problem domain You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? We await your feedback! -- Best regards, Antony Polukhin

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[process] Formal Review
by Raphaël Londeix 04 Nov '16

04 Nov '16

> > We encourage your participation in this review. At a minimum, kindly state: > - Whether you believe the library should be accepted into Boost > YES > * Conditions for acceptance > The interface used to spawn processes should be reworked. > - Your knowledge of the problem domain > I have implemented some process wrappers many times. I have used the last release of Boost.Process (0.5 I think?). > - What is your evaluation of the library's: > * Design > I think the similarity with the boost::thread api is a great choice. The lifetime of process is handled by small functors that will be called at specified times. I think is a very good design as it allows one to write small "plugins" in order to affect the setup or the tear down of a process. The integration with Boost.Asio follows the previous choice of using boost::thread as a reference, i.e. the child process is not the resource you read from/write to, you need some separate stream objects whose lifetime are tied to the child process: struct MyProcess { bp::async_pipe std_in; bp::async_pipe std_out; bp::async_pipe std_err; bp::child child; }; I haven't seen a way however to be asynchronously notified when a child exited, so I'm not sure how one would handle gracefully multiple async_read/write while the process could exit at any time. The choice of having a nice interface to spawn processes have been discussed already, but I still think that the library should aim to have the simplest and lowest level interface. IMO, C++ users do not need to have a nice and expressive syntax to spawn process, I cannot imagine a code base where many processes are launched at many places in the code. In other words, I think that either you rarely need to spawn a process (a hack for example), or your job is to spawn processes (a shell, a make clone, ...). In both cases, you will spawn processes in very few places in the code. Moreover, this interface style has an implication on build times, errors seen at build time and makes it hard to use in cases where your program needs to spawn processes based on runtime decisions. if one decided to implement a shell that supports redirections, pipes, environment modification and background jobs, they would certainly need to make runtime adjustments to the arguments given to child constructor. As of today, this has to be worked around by the user ; I think this should be the primary interface. A suggestion has been made to have a more idiomatic C++ construction, I would extend it with a specific options type: auto options = bp::options().args("gcc"); if (verbose) options.append_arg("-v"); if (ignore_errors) options.std_err.redirect(bp::null_device); bp::child child(io_service, std::move(options)); This way you make it impossible to modify the options after the child process creation. But that's just an idea :) * Implementation > The implementation is clear, but the support for the aforementioned constructor interface "leaks" into the implementation everywhere. As the previous version of Boost.Process, the different OS support is nicely separated and each stage of the process creation is clearly implemented in its own header. > * Documentation > The asynchronous section feels a bit short given the many possibilities the interface gives us. > * Tests > Didn't check > * Usefulness > I think it would be very useful to have something we can rely on instead of our own half baked implementations. > - Did you attempt to use the library? If so: > * Which compiler(s) > g++4.8 using c++11 > * What was the experience? Any problems? > I had many problems and decided to fallback on popen(). The first kind of problems were some compile errors. But the author kindly stated that I needed the HEAD of boost (which is not an option for me) but I found a workaround by not using some niceties of the interface: https://github.com/klemens-morgenstern/boost-process/issues/20 https://github.com/klemens-morgenstern/boost-process/issues/21 As said previously, for someone not used to boost.fusion, the errors are hard to read. The other problem that made me give up (temporarily) on using Boost.Process was the fact that asynchronous reads where unreliable when more than one process is spawned. https://github.com/klemens-morgenstern/boost-process/issues/22 This issue has been closed despite the fact that it is not fixed. - How much effort did you put into your evaluation of the review? > I'd say half a day counting this mail and the testing I made. Cheers, -- Raphaël Londeix http://hotgloupi.fr

2 1

[process] Formal Review
by Klaim - Joël Lamotte 03 Nov '16

03 Nov '16

Boost.Process Review ==================== ...At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance YES it should be accepted, though documentation need improvements. - Your knowledge of the problem domain I implemented naive and less naives ways to manage different processes in the past. I currently work on libraries which are all about multi-process communication and we have a poor-man's process management (launching, tracking, etc.) api that I have to maintain on Linux, Windows and MacOSX. I also have home projects which are organized as client-server with master-slave relationship, clients spawning servers and pinging them to keep processes alive mutually (using network communication). So basically, I implemented basic process management libraries, but I'm more a process management library user, in all my projects, paid or not. I have been exposed to a lot of problems related and solved a lot of them. I also used the last 2 Boost.Process versions proposed to Boost (though I voted no for these ones) but in cases where I just needed a cross-platform way to launch an arbitrary executable (no tracking nor communication). You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design The weird choice of variadic arguments in launching functions have been explained so I'm more at ease with it, though maybe ways to simplify it could be attemted in the future. I like that the design of boost::process::child follow, where it make sense, the design of std::thread. Both could be considered as execution resource, so it's fine to me that they share similar interface phylosophies of design (like spawning on construction and move-only). I would love it if there was a way (even slow) to track processes lifetime for processes that I don't have code for. Though it's ok for me if it's a future extension. I like the minimalism of the scope, though useful extensions could be added later. * Implementation I briefly eyescanned the code, looked more closely at the termination trigerriung code because of the discussion we had on termination reqest vs kill. I don't bother much about performance for this library as launching processes is rarely done in a tight high-performance loop. * Documentation I did a report of the documentation a few weeks or months ago, I do not know if changes have been made since. Anyway I think the documentation should have a part focused on explaining the concepts because even if most programmers knows what a process is, all related concepts (like what is the "environnement") are so specific to processes that they are often ignored as long as naive usage works. So as soon as the user need more specific usage, most, I believe, will not know what word to use to find the right concept. I think this library documentation should follow something similar to Boost.MSM which introduce to the basic concepts, though without walls of text. * Tests I didn't have time to try it yet in real applications, but so far didn't find any problem in basic usage. * Usefulness It is very useful for almost all my projects. - Did you attempt to use the library? YES If so: * Which compiler(s) Visual Studio 2015 for now. * What was the experience? Any problems? I only did minimal testing, nothing deep, no problems. - How much effort did you put into your evaluation of the review? Several hours diffused through several months. Joël Lamotte

1 0

[test] tests in master failing
by Aparna Kumta 03 Nov '16

03 Nov '16

I'm seeing the following error in the master branch compiling with Oracle Developer Studio. # Running Boost.Build tests Traceback (most recent call last): File "run.py", line 71, in <module> runner(root) File "/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_regression_src/regression.py", line 287, in __init__ self.main() File "/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_regression_src/regression.py", line 624, in main getattr(self,action_m)() File "/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_regression_src/regression.py", line 589, in command_regression self.command_test() File "/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_regression_src/regression.py", line 368, in command_test self.command_test_boost_build() File "/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_regression_src/regression.py", line 410, in command_test_boost_build "boost/bin.v2/libs/any/test/any_test.test")); OSError: [Errno 2] No such file or directory: '/export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/results/boost/bin.v2/libs/any/test/any_test.test' Looking at the bjam.log file I see: /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/kernel/modules.jam:107: in modules.call-in ERROR: rule "Jamfile</export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_root>.python-tag" unknown in module "Jamfile</export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_root>". /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/util/indirect.jam:98: in indirect.call /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/build/virtual-target.jam:455: in _adjust-name /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/build/virtual-target.jam:253: in abstract-file-target.__init__ /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/build/virtual-target.jam:561: in class(a)file-target.__init__ /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/kernel/class.jam:90: in class.new /export/home/sstrunk-tester/boost_regression/boost_regression_master/boost_intel-S2_cpp11/boost_bb/src/build/generators.jam:558: in generated-targets ... Has anyone else seen this? Thanks, Aparna

3 2

[filesystem] Move constructor from string_type
by danny kabrane 03 Nov '16

03 Nov '16

Hi all, boost::filesystem::path has 2 constructors from a string_type, one with a const reference and another one without const (wich I find troubling), but there's no constructor from a rvalue string_type. Is there something planned to add a move constructor from a string_type ? Regards Danny

2 1

[build] Annoying warnings from Asio, -isystem from bjam?
by Vinnie Falco 02 Nov '16

02 Nov '16

When I have "-Wunused-variable" I get these highly annoying warnings from boost/asio/error.hpp which I'm sure almost everyone has seen: boost_1_60_0/boost/asio/error.hpp:258:45: warning: ‘boost::asio::error::system_category’ defined but not used [-Wunused-variable] static const boost::system::error_category& system_category I don't want to disable the warning but I also don't want the false positives. Thankfully, clang and gcc have this wonderful option "-isystem" which lets you mark include paths as belonging to the system. This prevents warnings from being emitted that the programmer can do nothing about. How can I get Boost.Build to add the Boost library header search paths using "-isystem" so that gcc doesn't report warnings in Boost headers that I cannot do anything about? More detail here: http://stackoverflow.com/questions/1867065/how-to-suppress-gcc-warnings-fro… I've played around with <sysinclude> but can't seem to figure it out. Here's my Jamroot (my project builds on its own, without putting it in the Boost tree): https://github.com/vinniefalco/Beast/blob/master/Jamroot#L80 -- Follow me on Github: https://github.com/vinniefalco

2 2

[algorithm]Interface for search algorithms
by Зайцев Александр 02 Nov '16

02 Nov '16

1 0

[release] 1.63.0 closed for major changes
by Daniel James 02 Nov '16

02 Nov '16

Hi, The master branch is closed for major changes. In one week (9th Nov) it will be closing for the beta release. The full schedule is on the website: http://www.boost.org/development/ And if you haven't done so yet, please can you add your libraries' details to the release notes at: https://github.com/boostorg/website/blob/master/feed/history/boost_1_63_0.q… Or email them to me, if you don't like writing quickbook.

1 0

Curiousity question
by Edward Diener 01 Nov '16

01 Nov '16

I would like to ask a design question for any Boost developers or anyone on this mailing list who might care to answer. You are designing or working on a library, perhaps for Boost, perhaps for fun, and part of the design of the library has some public functionality taking a shared pointer as input. You: 1) Use boost::shared_ptr 2) Use std::shared_ptr 3) Use both boost::shared_ptr and std::shared_ptr with the same functionality 4) Use neither, you roll your own shared pointer-like functionality 5) You don't lke shared pointers and use raw pointers instead I really am curious about this. I haven't put any limitation on your library or made any presumption on who your library is for, on purpose. Thanks for anyone answering !

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[process] Formal Review starts today, 27 October
by Remi Chateauneu 31 Oct '16

31 Oct '16

Hi All, "Whether you believe the library should be accepted into Boost" It could be, but as some very important features are missinge, the implementation should be prepared from now on. "Your knowledge of the problem domain" About 20 yrs C++ development Linux and Windows. This library has a strong focus on the streaming which is quite rare and interesting. However, other very important features of multi-processing are missing should be planned: At least to ensure that, in the future, they can be added without breaking existing code. Example of these desired fatures are (Taken from my own needs) * List of subprocesses of a given process. * Get its parent pid (Already discussed). * Get the entire process tree of a machine. * It is very useful to be notified when a given process dies (unotify on Linux). * On windows, we have the feature e.startup_info.dwFlags = STARTF_RUNFULLSCREEN, which gives some control on the console, which Is very good. Could we have more documentation about it, and plans to have the same feature on Linux ? Generally speaking have some control on the process terminal if there is one. * Have some knowledge about users and user groups, as strings and integer identifiers: the concept is similar on Windows and Unix. * Have some control on process priority( Unix's nice command ) Indeed, many of these features are not portable, but most of time, developers use only a common core of features, which is quite enough. Maybe take inspiration from portable libraries such as Python psutil, which exposes a common interface for all operating systems. Interoperability: * It might be worth checking portability with other operating systems. BSD ? VMS ??? * Must ensure that this lib is interoperable with boost::interprocess (Concept of permissions might be worth using ?) * Does it build on pre-C++11 compilers ? Many projects are not able to upgrade to C++11 immediately and have to stick to previous C++ standard. Some critics (Nothing is perfect): * The merit of the ">" operator for optional arguments is to be visually similar to an indirection, but in the context of C++ programming, although elegant, it is I think confusing and could be mismatched with <> templates or comparisons. Creating a process is a not-so-frequent operation and we should not be afraid to be verbose and very clear, I believe. * Syntax ‘(bp::std_out & bp::std_err) > "output.txt"’ . Can we explain the exact difference with the syntax: ‘bp::std_out > "output.txt", bp::std_err > "output.txt"’’ * More comments in the code and examples please. * Examples async_io.cpp or arg.cpp do not build with boost 1.62: include\boost\process\detail\windows\compare_handles.hpp(24): error C2039: 'BY_HANDLE_FILE_INFORMATION_': is not a member of 'boost::detail::winapi' * ‘typedef basic_environment<wchar_t> wenvironment;’ : Is It really useful ?? POSIX getenv() only uses char. * Why is the class basic_environment so big, as it is basically a simple std::map< std::string, std::string > ? (Naïve question). Anyway, many congratulations for this very interesting work, which is definitely on the right direction. Regards

2 1

[gil] Some documentation links broken
by Edward Diener 31 Oct '16

31 Oct '16

In the documentation for Gil the links to the video tutorial, as well as the Information links on the left hand side of the initial page, are broken. Does anybody know if these links still exist anywhere ?

1 0

libstdc++ debug mode
by Robert Ramey 31 Oct '16

31 Oct '16

Back on May 2 2016 I made what I thought was an innocuous change to the serialization library build. I then forgot about it. I ran my tests and normal on my OSX set up for the compilers that I use there - clang and g++ 5.1 in various modes 03, 11 etc. Things seemed fine. I uploaded the develop branch as normal. Sometime later I discovered that all the gcc tests on linux platforms were failing with a segfault. Unfortunately time had passed and I couldn't run the tests myself so I never could figure out what the breaking change was. Lately I separated time to get to the bottom of this and in installed via Parallels ubuntu v 14 on my Mac as a guest operating system. After the usual back and forth getting stuff to work I was able to reproduce the problem. Running gdb indicated that things crashed with a call to boost::io::state_saver which led me to investigate THAT library which as it turned out is also failing all it's tests on the plaform. So thought I - no problem - all I have to do is to complain to the author of that library. But this didnt' workout a) I posted message and no one responded. b) I checked trac items and there was what seemed a related item. But it seemed a little hard to understand/fix and in any case, no one addressing it. I looked into just fixing it myself, but it looked to entail delving into the bowels of libstd++. So this dissuaded me as I have my own bowels to delve into. c) So I commented out references to boost::io::state_saver an ran some tests - and damn still failed. d) So I rolled back my source to the master dated 24 April 2016 and incrementally updated and ran some tests until I found the culprit. Needless to say, this is quite a tedious procedure. The issue seems to be that I added the following to the jamfile: <toolset>gcc:<define>_STLP_DEBUG <toolset>gcc:<define>_GLIBCXX_DEBUG The second adds a lot of checking. commenting this permitted tests to pass. Lesson of all this is: a) I'm thinking we should run all tests on the deelop branch with _GLIBCXX_DEBUG defined. That is, our jam files should contain?: <toolset>gcc:<variant>debug><define>_GLIBCXX_DEBUG b) it looks like when an error in libstd++ is encounted - things just segfault. I couldn't find the corresponding source in libstd++. GDB just bailed when I made a call to state_saver. c) boost::io::state_saver should be maintained. d) It would be helpful to be able to roll back the test matrix to any previous git version. That is, the results would be put into a database or datacube and we could scroll back and forth to see track down problems in test results. Robert Ramey

3 3

Review Manager needed for stacktrace library
by Antony Polukhin 27 Oct '16

27 Oct '16

Hello, Stacktrace is a C++98 library for storing and printing backtraces. Supports major platforms, does demangling, has API for accessing individual frames, supports hashing and comparison operators. Library: https://github.com/apolukhin/stacktrace Docs: http://apolukhin.github.io/stacktrace/index.html Anyone wishing to become the Review Manager for the library? -- Best regards, Antony Polukhin

8 21

[preprocessor] PR decision for Intel C++ 17 on up on Windows
by Edward Diener 27 Oct '16

27 Oct '16

I need some guidance from Boost developers in general. A PR has been issued for Boost PP which only affects Intel C++ 17 on up in Windows. I can ascertain that only this compiler in Windows is affectd by the PR. Needless to say I do not test this personally because it costs a decent amount of money to buy a license. Intel does graciously offer free licenses for Intel C++ on Linux for Boost developers and I have used it to test the compiler under Linux. Also there are no regression tests for Intel C++ on Windows in the 'develop' or 'master' regression test matrices. While the person who issued the PR ascertains that it fixes problems for Boost libraries he uses with Intel C++ 17 on Windows the nature of the PR is drastic enough that it could easily break other libraries if the changes in the PR does not correspond to Intel C++ preprocessing in all cases. So my quandary is what to do about the PR. The PR is at https://github.com/boostorg/preprocessor/pull/9#issuecomment-256741882. It is another one of these cases, like clang targeting VC++, where a compiler implementation on Windows wants to emulate the non-standard VC++ preprocessor but can't quite get it right ( as if emulating a broken preprocessor should ever be right ). Thoughts ? Ideas ? Suggestions ?

3 4

Boost odeint 1.62 link broken
by Daniel Duffy 27 Oct '16

27 Oct '16

________________________________________ From: Boost [boost-bounces(a)lists.boost.org] on behalf of Karsten Ahnert [karsten.ahnert(a)googlemail.com] Sent: 16 May 2016 15:08 To: boost(a)lists.boost.org Subject: Re: [boost] Boost 1.61.0 has been released > The Asio link http://www.boost.org/doc/libs/1_61_0/libs/asio/ is broken > (on http://www.boost.org/doc/libs/1_61_0/) I get ERR_TOO_MANY_REDIRECTS > with Chrome. The odeint link is also broken. I get "404 Not Found File "/home/www/live.boost.org/common/code/../../doc/archives/boost_1_61_0/libs/numeric/odeint/doc/html/index.html" not found. Unable to find file." Karsten _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

2 1

[boost.process] Review
by Klemens Morgenstern 27 Oct '16

27 Oct '16

Boost.Process 0.6, as can be found here (https://github.com/klemens-morgenstern/boost-process) will be in review from October 27 to November 5. The review manager will be Antony Polukhin. Doc (http://klemens-morgenstern.github.io/process/) I really hope this library gets through the review, since boost (or C++ for that matter) really needs a process library. I would be really happy, if some of you could take the time to look into it - if you find any major issues, they might be addressed, before the actualy review. That would then increase the probability of the library getting accepted.

5 13

[release] 1.63.0 now closed for new libraries and breaking changes
by Daniel James 27 Oct '16

27 Oct '16

Hello all, The master branch is now closed for new libraries and breaking changes, and will be closing for major changes in a week (2nd Nov) and closed for the beta in two weeks (9th Nov). 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_63_0.q… thanks, Daniel

2 3

[fixed_point] First presentation from GSoC 2015 and more
by Christopher Kormanyos 25 Oct '16

25 Oct '16

Hello Boost developers, A partial implementation of fixed-point in a Boost-like style based on proposal N3352 is now available.This work is the result of developments from 2013-2016, including efforts from GSoC 2015. The source code is available at: fixed_point-masterPreliminary docs are available at: fixed_point-docWe are potentially interested in submitting this work for inclusion in Boost. We are now requesting comments and suggestions for improvements, corrections and any further test results if these become available.Some key library features include:* proper C++ header-only implementation * full numeric_limits and <cmath> functions * flexible template choice of split between resolution and range * automatic selection of underlying integral representation * portability and high efficiency for bare metal microcontrollers * interoperation with Boost.Math * seamless extension to high-precision using Boost.Multiprecision * extensive test suite Thank you for your consideration. Best regards,Christopher Kormanyos

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[serialization] 2 blocking bugs
by alainm 25 Oct '16

25 Oct '16

Hi, My Boost.MPI builds are currently failing because of two blocking bugs in serialization (merge request 47 and 46). Could someone have a look please ? Thanks Alain

1 0

boost @ Meeting C++ 2016
by Jens Weller 24 Oct '16

24 Oct '16

Hello boost community, a short and final reminder, that the Meeting C++ conference is just a few weeks away! A few tickets are still available, here is the schedule: https://meetingcpp.com/index.php/schedule16.html The schedule also has the link to the student program and diversity tickets! Also there is still a few places available in the boost workshop with Boris Schäling and Michael Caisse. I plan to have a meetup for boost users in one of the breaks in the upper lounge, so that the boost communtiy is able to actually meet at Meeting C++! thanks, Jens Weller

1 0

Interest in chained relational operations
by Rahman Salim Zengin 24 Oct '16

24 Oct '16

Hi, The code in question is a simple chained comparison implementation. It works with any type If relational operators for that type is defined. https://github.com/rszengin/chain May some people find it useful?

4 4

predef: BOOST_COMP_MSVC defined for Gcc/Linux?
by Oliver Kowalke 24 Oct '16

24 Oct '16

Hi, test '#if defined(BOOST_COMP_MSVC)' evaluates to true with GCC on Linux. what I'm missing? Oliver

2 2

[interprocess] interprocess_condition blocks on notify_all if other process crashes
by Remi Chateauneu 22 Oct '16

22 Oct '16

When two processes share memory, and if one of them dies leaving a mutex in locked state, then the other process blocks on a notify using a interprocess_condition, stored in shared memory. This is described here: http://stackoverflow.com/questions/18240263/boost-interprocess-condition-bl… The reason is that this condition uses in general, a ipcdetail::spin_condition. Here is what it does in boost/interprocess/sync/interprocess_condition.hpp and boost/interprocess/sync/spin/condition.hpp : inline void spin_condition::notify(boost::uint32_t command) { //This mutex guarantees that no other thread can enter to the //do_timed_wait method logic, so that thread count will be //constant until the function writes a NOTIFY_ALL command. //It also guarantees that no other notification can be signaled //on this spin_condition before this one ends m_enter_mut.lock(); It locks an internal mutex, and if it is already locked and not unlocked by the crashed process, we are blocked. A fix is to replace lock() by: if( ! m_enter_mut.timed_lock(delay) ) throw an_exception(); A cleaner fix would be to derive a subclass from spin_condition to implement something like: bool derived_spin_condition::timed_notify(boost::uint32_t, ptime delay) What do you think ? Thanks.

2 1

[config] Changes to reflect Visual C++ "15" preview 5
by Beman Dawes 21 Oct '16

21 Oct '16

Boost.Config is current reporting these macros for msvc 14.0 update 3 and later: BOOST_NO_COMPLETE_VALUE_INITIALIZATION Xiang Fan of the VC++ compiler team kindly tested "15" preview 5 against boost without this macro is still getting errors. So this one is still needed. BOOST_NO_CXX11_HDR_CODECVT That's wrong. <codecvt> has been supplied at least since msvc 10.0. I'll submit a P/R. BOOST_NO_CXX14_AGGREGATE_NSDMI Here is a test program, based on the config docs: #include <cassert> struct Foo { int x, y = 42; }; int main() { Foo foo = { 1234 }; assert(foo.y == 42); assert(foo.x == 1234); } That now passed on "15" preview 5, so I'll summit a P/R. BOOST_NO_CXX14_CONSTEXPR The "15" preview 5 release notes say "The most notable compiler changes include complete support for generalized constexpr" I know from conversations with msft folks that they put a lot of effort into constexpr fixes, and that they would like bug reports if anyone is finds constexpr bugs with "15" preview 5. I'll submit a P/R. BOOST_NO_TWO_PHASE_NAME_LOOKUP This one still applies. The backstory has changed a lot, however. Enough progress has been made on the new parser that two phase name lookup should ship next year, and maybe even early next year. But don't hold your breath quite yet. Thanks to Andrew Pardoe for fact checking a draft of this post. --Beman

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Review Manager needed for the C++14 Reflections Library that works Without Macro nor Markup (ex magic_get)
by Antony Polukhin 20 Oct '16

20 Oct '16

Hello, PFR is a C++14 library that represents POD structures as tuples and provides tuple-like methods for PODs. Library has a set of predefined operators for PODs and useful functions for everyday use. Works with user-defined types without any macro nor boilerplate code. Has additional (theoretical) features for C++17. Library: https://github.com/apolukhin/magic_get Docs: http://apolukhin.github.io/magic_get/ Boost Library Incubator: http://blincubator.com/bi_library/pfr-pod-flat-reflection/?gform_post_id=16… Anyone wishing to become the Review Manager for the library? -- Best regards, Antony Polukhin

3 3

[spirit][qi] How to write a boost::spirit::qi parser to do what '?' does in regex?
by Han Wang 19 Oct '16

19 Oct '16

Let's say we have a regex "start:(?: ([0-9]{1,2}))? ([0-9].*)". It will match std::string string1 = "start: 01 0ab"; and std::string string2 = "start: 0ab"; We can also get the 2 matched string respectively. I try to use boost::spirit::qi parser to parse string2 but it couldn't match. qi::rule<std::string::const_iterator, std::string()> rule1 = qi::repeat(1,2)[qi::digit]; qi::rule<std::string::const_iterator, std::string()> rule2 = qi::digit >> *qi::char_; std::vector<std::string> attr; auto it_begin = string2.begin(); auto it_end = string2.end(); if (qi::parse( it_begin, it_end, qi::lit("start:") >> -(qi::lit(" ") >> rule1) >> qi::lit(" ") >> rule2 >> qi::eoi, attr)) std::cout<<"match"<<std::endl; else std::cout<<"not match"<<std::endl; We can of course use a look-ahead operator to check what's behind rule1, but is there a more generic approach to implement regex operator '?' ? Thanks!

2 1

[container] small_flat_set and small_flat_map
by Sam Kellett 19 Oct '16

19 Oct '16

Given that Boost.Container has a small_vector now, would a piece of work that changed flat_set and flat_map to use small_vector<0> internally be feasible? I ask because I feel like if this was the case it would be almost trivial to expose flat_tree<N> through small_flat_set<N> and small_flat_map<N> types to provide the small size optimisation for these two containers.

5 8

Error in Review Schedule
by Emil Dotchevski 19 Oct '16

19 Oct '16

It seems like the entry for the Callable Traits library in http://www.boost.org/community/review_schedule.html links the PODs Flat Reflection documentation. Emil

2 1

Re: [boost] [fixed_point] First presentation from GSoC 2015 and more
by John McFarlane 19 Oct '16

19 Oct '16

> > Date: Thu, 13 Oct 2016 20:41:27 +0000 (UTC) > From: Christopher Kormanyos <e_float(a)yahoo.com> > > > I discuss P0106R0 (a revision to N3352) in my paper, the latest draft of > > which is always available here: https://github.com/ > > johnmcfarlane/fixed_point/blob/master/doc/p0037.md#p0106 > > I'm honestly not sure which approach is preferable overall. The set of > > features and qualities requested during SG14 and SG6 meetings is large > and > > conflicting. It includes minimal build times, minimal run-time overhead, > > every rounding and overflow strategy listed in P0105, decimal radix and > > support for specialized fixed-point instructions on embedded > architectures. > Hi John. Thanks for visiting this thread. > > My recommendation would be to limit the scope of the proposal > to a realistic level in the SGs so that we can end up with anything > at all within a reasonable time scale. We could consider back porting > some (but probably not all) of SG14's specified interface to Boost > if that helps move anything along. > A second pair of implementor eyes would be a huge help. I should point out that although it hasn't seen much attention lately, P0106 may still be active. (Frankly, the evolution of my design has been largely a process of slowly copying or facilitating all the most popular from Lawrence's proposal!) One problem P0037 faces - even if it were to be standardized - would be that alone, it only provides fixed-point arithmetic. It's designed to work with types that also solve arbitrary width, rounding and overflow but those types are not part of any proposal. In particular, without an arbitrary-width integer type, it's very difficult to use fixed_point<> safely. > > I was also wondering about decimal radix, but I don't know if it > might simply be better to identify those 80% of the most popular use cases and simply specify these. At least it would get the library > moving forward and people could use fixed-point in C++. This is basically what we tried to do with the GSoC project. > That makes sense. I at least want to have a solution which doesn't close the door on decimal in future additions. Here's my current plan: https://github.com/johnmcfarlane/fixed_point/blob/master/doc/p0037.md#non-b… > > >> In your work I've been experiencing some trouble with>> the division > routine. > > Can you elaborate? Was this recently? I've been trying out numerous > > strategies for arithmetic operators. My current preferred approach is to > > pad the left-hand operand before performing the division but that's only > > been checked in for a few months. > > I'm not sure about the design, and error on my side is a likely possibility. But division operator in the master branch seems like it does not pad before divide. This might give the wrong result. > I hope that's not the case but it's a tough operator to get right - especially with 32-bit operands. If you ever find a good example of this happening I'd be very interested in it. At least when using the elastic alias, precision loss should be avoidable (beyond inevitable approximation of rational numbers and x/0). tl;dr: The details of padding in the division operator follow... The padding is done on this line: https://github.com/johnmcfarlane/fixed_point/blob/91c3f2e272f9fd5e33ffb4dc2… It's on display in this test: https://github.com/johnmcfarlane/fixed_point/blob/1cc7ceaaff5422667ae962995… In the above test, the two operands have a single fractional digits. If operator/ did not pad the LHS, then the integer operation would be 126/8 which would lose precision. Instead, the LHS is promoted and shifted left by 8 bits. Then, integer division occurs and the value is stored with (hopefully!) no further shifts. > For division, I have used the following approach. * handle sign * extend n bits to 2n bits > * shift left by radix split plus one round bit * divide 2n / n -> n bits > * handle round and sign > So you're right this requires 64-bit extension for a 32-bit fixed-point unless you tackle the problem of two-component division, which I have done using a simplified version of Knuth long division. At the moment, this is only in develop branch. The compiler switch is BOOST_FIXED_POINT_DISABLE_WIDE_INTEGER_MATH. > This is core to the difference in approach between P0037 and P0106. I guarantee to use built-in integer math for any type specialized on built-in integers. I believe that types with arbitrary width can then be built upon this foundation using novel integer types. Here is an example using Boost.Multiprecision to express a Googol: http://johnmcfarlane.github.io/fixed_point/#boost fixed_point<> uses the same algorithm regardless of whether the `Rep` integer is an uint8_t or a 400-bit custom type. > > >> I also had some problems compiling on VC12 (but you don't target that > >> compiler anyway). So that's no big deal. > > > You will need a C++11-compliant compiler as sg14::fixed_point<> creates > > literal types. Lack of support for features like constexpr constructors > is > > the main obstacle to compiling under VC++ 2013 and earlier. > I actually agree with that approach. Either it uses C++11 or it does not. I don't see the need to cater to a specific older compiler for new library work. > It's a pragmatic choice. Three reasons are: * C++11 has everything I need to implement (with difficulty) a literal type. In particular, I can write most of my unit tests using `static_assert` which is the best thing ever! * Once you start returning novel specializations from your arithmetic operators, `auto` type deduction is essential to usability. * Many of my target users in SG14 are stuck with compilers which are behind the curve. > >> In your work you are using wrapped versions of elementary transcendental > >> functions designed for built-in float. You might appreciate our > hand-crafted > >> functions designed to be highly efficient in several digit ranges. > > > Yes! I would be very interested in seeing if I could adapt those > function. > We worked hard on these. And there are many good algorithms available in boost/fixed_point/fixed_point_negatable_cmath.hpp > > Having spent a non-trivial amount of time writing the simplest sqrt I could find, I appreciate the effort this must have involved. > Mine are placeholders and I've deliberately postponed the non-trivial task > > of adding cmath equivalents. It's come up - maybe a couple of times - > > whether these functions are desired and the response has been to just > keep > > the proposal narrow so they are not included. > > > There are interesting questions regarding how to implement some > functions. > > For example, you surely don't always want the same inputs and outputs > from > > functions involving angles. And hopefully these functions can be > constexpr > > - unlike existing functions. > I agree. > > Also, how have you approached the trade-off between speed and accuracy? I > > went for a very simple sqrt function which is adequate if the value is > > calculated at compile time but is likely not desirable at run-time. This > > isn't a problem that floating-point variants face. > > The elementary transcendental functions use many techniques including polynomial approximation, Pade approximation, Taylor series, > Newton iteration. For low digit counts, mostly polynomial approximation. We > express the coefficients directly as integral values of the fixed_point > representation and avoid as much as possible full division and multiply, > favoring integer div and mul. These functions are quite efficient. We have > not constexpr-ed them. But it looks like there is potential for that. > Writing constexpr functions in C++11 can be a big challenge. > > >> I have also benched our fixed_point on bare-metal embedded systems both > >> 8-bit and 32-bit with very satisfying efficiency results. This is a key > >> feature for our embedded users that might also be interesting for SG14. > > > My current aim is to match integer performance for common arithmetic > > operations when using built-ins. This leads to some situations where > > overflow is a big problem - but no worse than dealing with raw integers. > > I'm curious how you deal with multiplying two int-sized values together > > without resorting to wider, slower types.I was under the impression that > > P0106 types always widen to fit their values. > We have resorted to wider integer for internal mul and div or used higher > level algorithms when the compiler switch BOOST_FIXED_POINT_DISABLE_WIDE_INTEGER_MATH > is activated as mentioned above (develop branch only). > In our approach, full multiplication requires: * sign conversion > * left shift for round bit > * multiply n*n --> 2n bits * right shift and round * sign conversion > On a 32-bit system, a full 32*32 -> 64 mul is required. > This full multiplication approach can not achieve your desired efficiency > goal on 8-bit and 32-bitCPUs. Division uses similar approach. > > Multiplication and division with plain int or unsigned can achieve the > efficiency goal --- if it were not for handling rounding and overflow. > > In my current branch, I'm actually trying to get even closer to integer-level efficiency. No longer does 32-bit multiplication result in 64-bit results on systems with 32-bit integer. This means that overflow on 32-bit arithmetic operations is even more common. The solution is explicit casting to 64-bit or use of an integer type which auto-widens: http://johnmcfarlane.github.io/fixed_point/#elastic This is the toughest design issue I face - especially when combined with division. > > >> Thank you and best regards, Chris > > And thank you. Keep up the good work! > > John > Thanks again and best regards, Chris > > Cheers, John

4 7

[serialization]
by alainm 19 Oct '16

19 Oct '16

Hi, I have a few blocking compilation/link problems on the develop branch for which to fixes are pending (46 (3 lines) & 45(1 line)). 45 is a bug in the code I thin, 46 probably works just fine on most platform, but not on mine (recent Intel compiler on CentOS 6.5, which mean advanced features, but old headers). Boths are breaking are breaking some tests on Boost.MPI. Could someone have a look at it ? Regards Alain

1 0

[Serialization] check failed ???
by alainm 17 Oct '16

17 Oct '16

Hi, If I got on: https://github.com/boostorg/serialization/pull/46 I see a message "All checks have failed". If I follow the link "details" I see stuff regarding rake (?) and unfound "rakefiles", What is this all about ? Regards -- Alain Miniussi Pole Génie Logiciel Scientifique Observatoire de la Côte d'Azur Blv de l'Observatoire, Nice

1 0

Read only attributes in C++ (class proposal)
by Daniel Illescas Romero 17 Oct '16

17 Oct '16

Hello, I wanted to make some read only attributes on C++ so I made a class, named ReadOnly. This class will contain an internal private value, only “friend” classes could change this internally. Description: · A read only object will contains an internal value that can’t be changed outside the class. For example: ReadOnly<string> name = “Daniel”; To access its value: object.name, if you try: object.name = “other”, it won’t change it’s value because it’s a read only variable; you can change it’s value only inside the class the object is declared, you could change it like: name.value = “whatever”; · To set a value (outside the class) to a read only attribute you MUST specify a setter function (which can be static and contained inside the class), like: ReadOnly<int> age {ReadOnly::setAge, 1}; (optionally you can also set a default value to the attribute). Example of setter function: static bool setAge(const int& value) { return (value > 0 && value <= 150); } So if you you have an object and you want to change its value like this: object.age = 100; it will change its internal value only if the setter function (which is called internally) returns true. · The idea of doing all of this instead private variables and getters & setters is because this approach is closer to OOP than what is normally used; I mean if you have an object and you want to get an attribute value, what you need to do in most cases is something like: object.getAttribute(), you are calling a function to just take a look at an attribute, that shouldn’t make sense in OOP, that’s why I made all of this. It’s also similar to how you manage getters and setters in Swift, because they are embedded in the attribute and you don’t need to make other functions. :) I uploaded the project to github so everyone can take a look: https://github.com/illescasDaniel/ReadOnly <https://github.com/illescasDaniel/ReadOnly> — I wanted to know your opinion about the idea of the class and also about the implementation, I’d love to upload it to boost libraries but I want to know people opinion and make the class better. Thank you!

2 1

How can I detect if a template static member function exists?
by Vinnie Falco 16 Oct '16

16 Oct '16

I'd like to write a trait: template<class T> struct has_content_length : std::integral_constant<bool, ...>{}; which detects whether or not a template static member function is present in T. Here's a typical T: struct X { template<bool isRequest, class Body, class Headers> static std::uint64_t content_length( message<isRequest, Body, Headers> const& m); }; How can I detect if X::content_length(m) is callable for any m of type message template?

2 1

Re: [boost] [config] Changes to reflect Visual C++ "15" preview 5
by Tom Kent 15 Oct '16

15 Oct '16

I've now added a runner to the test suite with msvc-15.0 (preview 5 installed), it should show up in a couple hours as "teeks99-09o-win2012R2-64on64" (the far right column). The run only took a few minutes instead of an hour or two, so I'm expecting it to look pretty broken. Just glancing at the logs it looks like the compiler isn't even being found. Does this require b2 updates? Tom

2 1

[algorithm] New search algorithms
by Зайцев Александр 14 Oct '16

14 Oct '16

Hello. Now in Boost. Algorithm there are 3 algorithms for searching: Knuth-Morris-Prata, Boyer-Moore, Boyer-Moore-Horspool. They are good algorithms, but there are other efficient algorithms like Turbo-Boyer-Moore, Quick Search, etc. You can find some more here: http://www-igm.univ-mlv.fr/~lecroq/string/index.html Now i am working on new search algorithms for Boost.Algorithm. Maybe are there anybody,who familiar with string search algorithms? -- Best regards, Alexander Zaitsev

1 0

[program_options] -d directory is falling into positional input-files 1_62_0
by Roger Martin 14 Oct '16

14 Oct '16

Hi, Pulled this from a larger application to isolate to the problem: -d ./tmp or -d "./tmp" doesn't go to directory string but is with the positionals: #include <stdlib.h> #include <iostream> #include <exception> #include <string> #include <cstring> #include <memory> #include <fstream> #include "boost/program_options.hpp" int main(int argc, char** argv) { try { boost::program_options::positional_options_description p; p.add("input-file", -1); std::string directory = "./"; boost::program_options::options_description visible("Allowed options"); visible.add_options() ("input-file", boost::program_options::value<std::vector<std::string>>(), "input files can be *.xml, *.pdb, *.mol2, *.mtz, *.cif, *.csv, and *.sdf. Csv and sdf formats are for NMR calculations. csv lists the atoms for which the shifts will be computed. 1st line containts the Header: \"Chain\",\"Residue ID\",\"Sequence\",\"Atom Name\",\"Unbound ppm\",\"Bound ppm\". Then atoms may be listed i.e \"A\",\"MET\",231,\"CE\",10.30,10.50. sdf file contains the ligands for a CSP calculation. ") ("directory,d", boost::program_options::value<std::string>(&directory)->implicit_value("./"), "Directory for publishing output.") ; boost::program_options::options_description all("Allowed options"); all.add(visible);//.add(hidden); boost::program_options::variables_map vm; boost::program_options::store(boost::program_options::command_line_parser(argc, argv).options(all).positional(p).run(), vm); boost::program_options::notify(vm); std::vector<std::string> fileList = vm["input-file"].as < std::vector < std::string >> (); for (unsigned int fileListIndex = 0; fileListIndex < fileList.size(); fileListIndex++) { std::cout<<" "<<fileList[fileListIndex]<<" "<<std::endl; } } catch (std::exception& e) { std::cout << e.what() << std::endl; } return 0; } Built with g++ 4.9.0 on Linux frodo.quantumbioinc.com 2.6.32-573.7.1.el6.centos.plus.x86_64 #1 SMP Wed Sep 23 03:02:55 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux g++ -fPIE -std=c++11 -I${BOOST_HOME}/include -Wl,--allow-multiple-definition -MT main.o -MMD -MP -O3 -c -o main.o main.cpp g++ -pie -Wl,--allow-multiple-definition -o main main.o -L${BOOST_HOME}/lib -lboost_program_options -lc -lm -lpthread -lz -lstdc++ -ldl -lrt And run as ./main 2-aminoethanol.pdb -d ./tmp which results in 2-aminoethanol.pdb ./tmp This code had been working with 1_57_0. Some change in the API I need to adjust for?

1 0

[algorithm] Longest palindromic substring in Boost.Algorithm
by Зайцев Александр 14 Oct '16

14 Oct '16

Hello I want to add to Boost.Algorithm algorithm for finding all palindromes in a sequence in O(N). https://en.wikipedia.org/wiki/Longest_palindromic_substring Is it useful algorithm for Boost? Have you any suggestions? -- Best regards, Alexander Zaitsev

3 2

Re: [boost] [fixed_point] First presentation from GSoC 2015 and more
by John McFarlane 13 Oct '16

13 Oct '16

Hi Christopher. I'm actually the main culprit behind P0037. :) Date: Wed, 12 Oct 2016 18:32:26 +0000 (UTC) > From: Christopher Kormanyos <e_float(a)yahoo.com> > To: "boost(a)lists.boost.org" <boost(a)lists.boost.org> > Subject: Re: [boost] [fixed_point] First presentation from GSoC 2015 > and more > Message-ID: <1026507022.4306136.1476297146580(a)mail.yahoo.com> > Content-Type: text/plain; charset=UTF-8 > > > I'm a bit surprised I didn't see this work before. > > Are you aware that SG14, the gamedev, real-time simulations, embedded > > software and financing study group for the standard > > is working on fixed point real proposal too? > > Here is a version of the proposal:>http://johnmcfarlane > .github.io/fixed_point/papers/p0037r2.html and>http://johnmcfarlane.githu > b.io/fixed_point/papers/p0381r0.html > > I will notify SG14 in case they missed your work too. > Thanks for the information. > We became aware of your work unfortunately very late inthe project. Much > of our fixed_point work stems from myearly prototyping dating from 2011 - > 2013. > I see a lot of similarities in the two bodies of work.Maybe we could > identify the strengths of each work.I don't know if it makes sense to > combine them,but maybe share some concepts or interface ideaswould make > sense. > I discuss P0106R0 (a revision to N3352) in my paper, the latest draft of which is always available here: https://github.com/ johnmcfarlane/fixed_point/blob/master/doc/p0037.md#p0106 I'm honestly not sure which approach is preferable overall. The set of features and qualities requested during SG14 and SG6 meetings is large and conflicting. It includes minimal build times, minimal run-time overhead, every rounding and overflow strategy listed in P0105, decimal radix and support for specialized fixed-point instructions on embedded architectures. > > In your work I've been experiencing some trouble withthe division routine. Can you elaborate? Was this recently? I've been trying out numerous strategies for arithmetic operators. My current preferred approach is to pad the left-hand operand before performing the division but that's only been checked in for a few months. > I also had some problems compilingon VC12 (but you don't target that > compiler anyway).So that's no big deal. > You will need a C++11-compliant compiler as sg14::fixed_point<> creates literal types. Lack of support for features like constexpr constructors is the main obstacle to compiling under VC++ 2013 and earlier. > In your work you are using wrapped versions of elementarytranscendental > functions designed for built-in float.You might appreciate our hand-crafted > functionsdesigned to be highly efficient in several digit ranges. > Yes! I would be very interested in seeing if I could adapt those function. Mine are placeholders and I've deliberately postponed the non-trivial task of adding cmath equivalents. It's come up - maybe a couple of times - whether these functions are desired and the response has been to just keep the proposal narrow so they are not included. There are interesting questions regarding how to implement some functions. For example, you surely don't always want the same inputs and outputs from functions involving angles. And hopefully these functions can be constexpr - unlike existing functions. Also, how have you approached the trade-off between speed and accuracy? I went for a very simple sqrt function which is adequate if the value is calculated at compile time but is likely not desirable at run-time. This isn't a problem that floating-point variants face. > I have also benched our fixed_point on bare-metalembedded systems both > 8-bit and 32-bit with verysatisfying efficiency results. This is a key > featurefor our embedded users that might also be interestingfor SG14. > My current aim is to match integer performance for common arithmetic operations when using built-ins. This leads to some situations where overflow is a big problem - but no worse than dealing with raw integers. I'm curious how you deal with multiplying two int-sized values together without resorting to wider, slower types.I was under the impression that P0106 types always widen to fit their values. > > Thank you and best regards, Chris > > And thank you. Keep up the good work! John > > On Tuesday, October 11, 2016 11:37 PM, Klaim - Jo?l Lamotte < > mjklaim(a)gmail.com> wrote: > > > On 6 October 2016 at 12:07, Paul A. Bristow <pbristow(a)hetp.u-net.com> > wrote: > > > > -----Original Message----- > > > From: Boost [mailto:boost-bounces@lists.boost.org] On Behalf Of > > Christopher Kormanyos > > > Sent: 05 October 2016 23:07 > > > To: boost(a)lists.boost.org > > > Subject: Re: [boost] [fixed_point] First presentation from GSoC 2015 > and > > more > > > > > > >> A partial implementation of fixed-point in a Boost-like > > > >> style based on proposal N3352 is now available. > > > > > > > ... But your links don't work, > > > > Indeed :-( ( > > > > The correct link to the docs for some years used to be > > > > https://dl.dropboxusercontent.com/u/43940943/modular-boost/ > > libs/fixed_point/doc/html/index.html > > > > but sadly this no longer works for reasons that so far escape me (but I > > suspect some change at Dropbox?). > > > > Meanwhile here is a PDF version to whet your appetite until I get a html > > version publicly available. > > > > https://dl.dropboxusercontent.com/u/43940943/modular-boost/ > > libs/fixed_point/doc/fixed_point.pdf > > > > Boost.Fixed_point ? > > =============== > > > > A partial implementation of fixed-point in a Boost-like style based on > > proposal N3352 is now available. > > > > This work is the result of developments from 2013-2016, including efforts > > from GSoC 2015. > > > > The source code is available at: https://github.com/ > > BoostGSoC15/fixed_point > > > > (The master branch will be stable for a while but the develop branch may > > be updated in the light of your feedback). > > > > Preliminary docs are available at: > > > > https://dl.dropboxusercontent.com/u/43940943/modular-boost/ > > libs/fixed_point/index.html > > > > We are potentially interested in submitting this work for inclusion in > > Boost. > > > > We are now requesting comments and suggestions for improvements, > > corrections and any > > further test results if these become available. > > > > Some key library features include: > > > > * proper C++ header-only implementation > > * full numeric_limits and <cmath> functions > > * flexible template choice of split between resolution and range > > * automatic selection of underlying integral representation > > * portability and high efficiency for bare metal microcontrollers > > * interoperation with Boost.Math > > * seamless extension to high-precision using Boost.Multiprecision > > * extensive test suite > > > > Thank you for your consideration. > > Best regards, > > > > Christopher Kormanyos > > > > And apologies from Paul. > > > > > Hi, > > I'm a bit surprised I didn't see this work before. > Are you aware that SG14, the gamedev, real-time simulations, embedded > software and financing study group for the standard > is working on fixed point real proposal too? > Here is a version of the proposal: > http://johnmcfarlane.github.io/fixed_point/papers/p0037r2.html and > http://johnmcfarlane.github.io/fixed_point/papers/p0381r0.html > I will notify SG14 in case they missed your work too. > > Jo?l Lamotte > > _______________________________________________ > Unsubscribe & other changes: http://lists.boost.org/mailman > /listinfo.cgi/boost > > > >

2 1

Re: [boost] : Curiousity question
by Brian Wood 13 Oct '16

13 Oct '16

Edward Diener writes: > I would like to ask a design question for any Boost developers or anyone > on this mailing list who might care to answer. > > You are designing or working on a library, perhaps for Boost, perhaps > for fun, and part of the design of the library has some public > functionality taking a shared pointer as input. You: > > 1) Use boost::shared_ptr > 2) Use std::shared_ptr > 3) Use both boost::shared_ptr and std::shared_ptr with the same > functionality > 4) Use neither, you roll your own shared pointer-like functionality > 5) You don't lke shared pointers and use raw pointers instead > > I really am curious about this. I haven't put any limitation on your > library or made any presumption on who your library is for, on purpose. > Thanks for anyone answering ! I avoid shared pointers. I'll use a unique_ptr if a raw pointer won't work. -- Brian Ebenezer Enterprises - In G-d we trust. http://webEbenezer.net

2 1

[qvm] Doesn qvm contain any sse/avx etc optimizations?
by Viktor Sehr 12 Oct '16

12 Oct '16

If not, is it planned for utilizing it? /Viktor

2 1

Boost library incubator URL address
by Edward Diener 12 Oct '16

12 Oct '16

Is the Boost Library Incubator web site down or removed ? I cannot get to it anymore via a URL. I have this URL, http://www.rrsd.com/software_development/blincubator/index.htm, but it just hangs on me.

2 1

Announcing version 3 of the cxx_dual library
by Edward Diener 11 Oct '16

11 Oct '16

I have created version 3 of the cxx_dual library. version 3 is a large rewrite of the documentation to simplify the use of the library, as well as a change in the directory structure so that the basic usage of the library is through a single header file and the use of a namespace alias, and not through the macro interface. As in: #include <boost/cxx_dual/regex.hpp> void SomeFunction() { cxxd_regex_ns::regex re("A regular expression etc."); bool result(cxxd_regex_ns::regex_match("Some string...",re)); // etc. } What ! No macros ! Actually a few macros still exist for testing which dual library has been chosen and overriding the dual library chosen, but the basic functionality means almost no macros in user code. The library is available at https://github.com/eldiener/cxx_dual.git. What is it ? The Cxx Dual library, or CXXD for short, is a C++ macro header-only library which chooses between using a Boost library or its C++ standard equivalent library for a number of different C++ implementations, while allowing the end-user to use the same code to program either choice. An implementation is a Boost library which has a C++ standard library equivalent whose public interfaces are nearly the same in both cases. An 'implementation' is called a 'mod' for short and each of the possible Boost or C++ standard implementations for that mod are called a 'dual library'. The Cxx Dual library does this by automatically choosing either the Boost library or the C++ standard library for a particular mod, including the correct header file(s) needed for the dual library chosen, and creating a namespace alias for the namespace of the dual library chosen. CXXD also provides a macro-based solution for distinguishing between the Boost version and the C++ standard version of a dual library so that specific code for a particular dual library choice may be written in those cases where the public interfaces diverge.

1 0

Announcing version 3 of the cxx_dual library
by Edward Diener 11 Oct '16

11 Oct '16

I have created version 3 of the cxx_dual library. version 3 is a large rewrite of the documentation to simplify the use of the library, as well as a change in the directory structure so that the basic usage of the library is through a single header file and the use of a namespace alias, and not through the macro interface. As in: #include <boost/cxx_dual/regex.hpp> void SomeFunction() { cxxd_regex_ns::regex re("A regular expression etc."); bool result(cxxd_regex_ns::regex_match("Some string...",re)); // etc. } What ! No macros ! Actually a few macros still exist for testing which dual library has been chosen and overriding the dual library chosen, but the basic functionality means almost no macros in user code. What is it ?

1 0

Re: [boost] [beast] Request for Discussion
by Vinnie Falco 10 Oct '16

10 Oct '16

There's some great programming and design discussion related to Beast and HTTP going on in the GitHub issues for the project. And there are some interface changes looming. Stakeholders and interested parties should consider participating in these discussions if they would like to influence the outcome: Some of the discussions: HTTP 1 versus 2 namespacing https://github.com/vinniefalco/Beast/issues/121 HTTP/2 design https://github.com/vinniefalco/Beast/issues/122 Expect: 100-continue https://github.com/vinniefalco/Beast/issues/123 `basic_headers` to make better use of allocators and string_ref https://github.com/vinniefalco/Beast/issues/124

1 0

[git] some fetch errors
by Raffi Enficiaud 09 Oct '16

09 Oct '16

Hi all, I see the following errors: """ Fetched in submodule path 'libs/python', but it did not contain 0ca7db361b8a70540c5683ae3ba2219c3352f721. Direct fetching of that commit failed. """ while my agents were checking out version aa407db3a22120496d6c49d2e3bc0b494b5ceb76 of the boost superproject. Does anyone know why am I seeing this? I cannot find rev 0ca7db361b8a70540c5683ae3ba2219c3352f721 in libs/python Thanks, Raffi

5 6

[python] Missing test file.
by Rene Rivera 09 Oct '16

09 Oct '16

FYI.. The testing CI sanity check is failing with this missing file error: error: Unable to find file or target named error: 'printer.py' error: referred to from project at error: '../libs/python/test' <https://travis-ci.org/boostorg/boost/jobs/166196326#L6960> Please fix ASAP. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 1

Re: [boost] [beast] Request for Discussion
by Vinnie Falco 09 Oct '16

09 Oct '16

To get this topic hopping again, I'll share a bit of news. With help from Howard Hinnant I've opened an issue against the Networking TS to make sure that its algorithms do not place unnecessary requirements on user-defined types: http://cplusplus.github.io/LWG/lwg-active.html#2779 This will affect Beast's buffer sequence adapters (such as buffer_cat).

1 1

Boost.Python NumPy extension
by Stefan Seefeld 09 Oct '16

09 Oct '16

Hello, I'm happy to announce that I just merged the NumPy C++ wrappers from https://github.com/ndarray/Boost.NumPy into Boost.Python's development branch. (Online documentation for it can be browsed here: http://boostorg.github.io/python/develop/doc/html/numpy) I'd very much like to be able to merge this into the master branch for the next Boost release (version 1.63). At present I'm using SCons to build Boost.Python (stand-alone, against a separately installed Boost), which is also the infrastructure I use for CI testing (https://travis-ci.org/boostorg/python) I would like to ask for help with integrating the new NumPy extension into the Boost.Build-based build system, such that this will also be picked up by the regular Boost infrastructure. Please refer to https://github.com/boostorg/python/issues/89 if you'd like to help with this. Many thanks ! Stefan -- ...ich hab' noch einen Koffer in Berlin...

1 0

Build: Trying to get Boost.Build to see my OpenSSL on Windows
by Vinnie Falco 07 Oct '16

07 Oct '16

I'm trying to build the Asio SSL examples but bjam can't find my OpenSSL installation on Windows (using Visual Studio 2015). Everything else builds. And I am having the dickens of a time finding any information on the web about mixing Windows, OpenSSL, and bjam. As a last resort I've thrown a hail mary to StackOverflow: http://stackoverflow.com/questions/39800333/how-do-i-get-bjam-to-set-includ… I'm not clear on what this line does on Windows using MSVC: lib ssl ; The line appears in Asio Jamfiles that use OpenSSL. Any help is appreciated, thank you.

7 38

[doc] Doc directory for a library
by Edward Diener 07 Oct '16

07 Oct '16

If a library does not have a 'doc' subdirectory, because the doc is not buildable but is rather hardcoded into an HTML file, what is the best way to satsify Boost and the boost_check_library regression test for that library ?

2 2

Upcoming changes to _MSC_VER
by Gabriel Dos Reis 07 Oct '16

07 Oct '16

Hi, This is a heads up. I spoke with Beman at CppCon about this: the upcoming release of Visual Studio (VS "15") has some changes to how _MSC_VER will be defined at every (future) update. These changes are already implemented in 'VS "15" Preview 5'. The full details are here https://blogs.msdn. microsoft.com/vcblog/2016/10/05/visual-c-compiler-version/ Internal testing showed that some components of Boost source code needed a few changes to use inequalities instead of equalities with _MSC_VER. Thanks, PS: The formal documentation of _MSVC_LANG is coming. -- Gaby

3 3

Review request: Beast
by Vinnie Falco 04 Oct '16

04 Oct '16

Can Beast please be added to the review queue? Michael Caisse has volunteered to act as the review manager. Beast provides C++11, header-only implementations of the HTTP and WebSocket protocols using Boost.Asio and presenting a consistent, modern synchronous and asynchronous interface style. Beast project repository https://github.com/vinniefalco/Beast HTML documentation http://vinniefalco.github.io/beast Boost incubator link: http://blincubator.com/bi_library/beast-2/?gform_post_id=1579 Thanks!

3 3

Extending Boost.Python with NumPy support
by Stefan Seefeld 04 Oct '16

04 Oct '16

Hello, I'm presently working on a few improvements to the Boost.Python module. As part of this I'm refactoring the numeric API to actually support NumPy. There has been quite a lot of effort we put into this in the past (notably a GSoC project I mentored a few years ago), but we never managed to include this into the Boost master branch, so it's never been formally released. As I'm now getting ready to polish this work off, I wonder whether any of this would require a formal submission as a new Boost library, or whether it can just be done under the Boost.Python umbrella ? I reckon this is somewhat of a gray area, so I'd like to clarify whether there are concrete rules for what changes / additions require a formal review process. Thanks, Stefan -- ...ich hab' noch einen Koffer in Berlin...

5 8

Re: [boost] [Boost-users] Need help with errors while building boost for clang on android NDK
by Robert Dailey 04 Oct '16

04 Oct '16

On Wed, Sep 28, 2016 at 10:49 AM, Robert Dailey <rcdailey.lists(a)gmail.com> wrote: > On Mon, Sep 26, 2016 at 11:55 AM, Robert Dailey > <rcdailey.lists(a)gmail.com> wrote: >> On Mon, Sep 26, 2016 at 11:09 AM, Oliver Kowalke >> <oliver.kowalke(a)gmail.com> wrote: >>> 2016-09-26 17:57 GMT+02:00 Robert Dailey <rcdailey.lists(a)gmail.com>: >>>> >>>> >> > clang-linux.compile.asm >>>> >> > >>>> >> > >>>> >> > bin.v2\libs\context\build\clang-linux-android\release\link-static\runtime-link-static\target-os-linux\threading-multi\asm\make_i386_ms_pe_gas.o >>>> >> > libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:30:1: error: unknown >>>> >> > directive >>>> >> > .def _make_fcontext; .scl 2; .type 32; .endef >>>> > >>>> > >>>> > you try to build for i386 instead arm >>>> >>>> How can I make it use arm instead? >>> >>> >>> I assume you try to cross compile : >>> http://www.boost.org/doc/libs/1_61_0/libs/context/doc/html/context/architec… >> >> I am indeed trying to cross compile, however I am not familiar with b2 >> nor do I much care to learn it (since it's a means to an end for me to >> build boost). >> >> Can you provide an example of how I can specify the documented >> settings to b2 for my build? Do I provide the values to those in my >> project-config file? > > Would really love help with this guys. I literally can't find info on > this anywhere else. Surely someone has had success getting 1.61 > building with NDK + ARM + Clang. > > I made a best-guess using the context cross compiling settings linked > earlier. Does this seem correct? It doesn't build at the moment saying > it can't find locale-related symbols. That doesn't help me at all so I > guess I'm going to have to dig into the llvm STL code and find out > what preprocessor flags I'm missing (assuming it's that simple). Also > I still don't know how to specify 'ar' and 'ranlib' executables to > boost from NDK. > > > using clang : android : > $(androidNDKRoot)/toolchains/llvm/prebuilt/$(androidPlatform)/bin/clang++ : > <compileflags>--sysroot=$(androidNDKRoot)/platforms/android-15/arch-arm > <compileflags>-Os > <compileflags>-fno-strict-aliasing > <compileflags>-O2 > <compileflags>-DNDEBUG > <compileflags>-g > <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++abi/libcxxabi/include > <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++/libcxx/include > <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++/libs/armeabi-v7a > <compileflags>-I$(androidNDKRoot)/sources/android/support/include > <compileflags>-DANDROID > <compileflags>-D__ANDROID__ > <compileflags>-D__arm__ > <compileflags>-D_REENTRANT > <architecture>arm > <address-model>32 > <binary-format>pe > <abi>aapcs > ; FYI: I still haven't gotten this working. Sorry to keep bumping this thread but I have absolutely zero options yet. I need help from the boost developers at this point, I think.

2 2

[concept_check] convert Concept to trait?
by Vinnie Falco 04 Oct '16

04 Oct '16

I don't see a place to open issues on https://github.com/boostorg/concept_check so I am posting this here. What I want to do is convert a concept into a trait. For example, given the ForwardIterator concept checking class, I would like to write: template<T> using is_ForwardIterator = std::integral_constant<bool, ...>; Which aliases to std::true_type if T meets the requirements of ForwardIterator and false otherwise. Or perhaps a general purpose alias: template<t> using is_concept<T, C> = std::integral_constant<bool, ...>;l Which aliases to std::true_type if T meets the requirements of concept C. Are such things possible, or perhaps already in the library? My preliminary analysis suggests the answers to these questions are no and no. Has this point been brought up elsewhere, and if so where could I find it? Regards

3 2

preparation for Gsoc 2017
by Prashant Kumar 04 Oct '16

04 Oct '16

Hello Boost community, I need some help for preparing effectively for Gsoc 17 with Boost community. I have been through the boost gsoc webpage and for getting selected in Gsoc an aspirant need to provide competency Test. I want to know that apart from competency test what other projects would be helpful in making my proposal strong. Should I be writting more programs using boost library ? , should I be aware of all boost libraries ?. I want your suggestions as I'm very serious regarding the matter. thanks!! and sorry if the question is quite nooby.

2 1

How to build Boost with VS15
by Olaf van der Spek 04 Oct '16

04 Oct '16

Hi, How does one build Boost (1.62) with VS15 (Preview 4)? I know it's not officially supported.. C:\VC\boost>bootstrap.bat Building Boost.Build engine 'cl' is not recognized as an internal or external command, operable program or batch file. Failed to build Boost.Build engine. Please consult bootstrap.log for further diagnostics. -- Olaf

6 10

Review Request: Synapse
by Emil Dotchevski 03 Oct '16

03 Oct '16

I'm requesting a formal review for the Synapse library. Edward Diener has kindly offered to serve as the review manager for Synapse. Synapse is a signal programming library, similar to Boost Signals2 and the signals-slots system in Qt. The main difference is that Synapse is non-intrusive: the address of any object of any static type whatsoever can be passed to synapse::emit to emit a signal. This makes it possible to emit Synapse signals from objects of third-party types as well as system objects (e.g. standard FILE pointers, HWNDs, etc.) or any other object that can be converted to a pointer. The library has been formatted to fit the Boost directory and namespace structure. To get Synapse, clone https://github.com/zajo/boost-synapse.git into a directory called synapse under your boost/libs directory. See the tutorial at http://zajo.github.io/boost-synapse/Tutorial.html, or read full documentation at http://zajo.github.io/boost-synapse/index.html. Thanks, Emil

1 0

CMake Modularization
by Philip Woods 03 Oct '16

03 Oct '16

CMake is a widely used build system and has become for many the de facto standard. Boost is a widely used collection of modules and has become for many part of the de facto standard. However, the two do not play very well together. I know there is another port of boost to CMake, but it has lain dormant for years and uses an old version of boost; plus I chose to take a different route. The old project attempted to completely replace Boost.Build with CMake. My example port simply allows people to more easily use boost modules in their projects. I created an example project https://github.com/Elzair/cmake-boost-filesystem-test to demonstrate my ideas. I added CMake build support to the minimum number of modules needed to support this demo: https://github.com/Elzair/assert https://github.com/Elzair/config https://github.com/Elzair/core https://github.com/Elzair/filesystem/tree/master and https://github.com/Elzair/system I even added CMake build support to the header only boost libraries. I did this for two reasons. First, I did not want users to have to fool with CMake's find_package(). Second, I wanted to add helpful error messages in case a user has not included all of a module's dependencies (or added them in the wrong order). Would the community be interested in modular CMake support for more modules? Any comments, questions, critiques or suggestions are welcome.

8 16

Cannot open include file: 'pyconfig.h'
by Olaf van der Spek 30 Sep '16

30 Sep '16

Hi, Boost 1.62 @ VC15, no Python installed: call "C:\Users\W7\AppData\Local\Temp\b2_msvc_default_vcvarsall_x86.cmd" >nul cl /Zm800 -nologo @"bin.v2\libs\python\build\msvc\debug\link-static\threading-multi\import.obj.rsp" ...failed compile-c-c++ bin.v2\libs\python\build\msvc\debug\link-static\threading-multi\import.obj... compile-c-c++ bin.v2\libs\python\build\msvc\debug\link-static\threading-multi\exec.obj exec.cpp C:\VC\boost\boost/python/detail/wrap_python.hpp(50): fatal error C1083: Cannot open include file: 'pyconfig.h': No such file or directory Should it be trying to build Python stuff? -- Olaf

1 0

[release] Boost 1.62.0 release available
by Rene Rivera 30 Sep '16

30 Sep '16

Release 1.62.0 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 two new libraries and numerous enhancements and bug fixes for existing libraries. New Libraries * Fiber: Framework for userland-threads/fibers, from Oliver Kowalke. * QVM: Boost QVM is a generic library for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications, from Emil Dotchevski. For details, including download links, see http://www.boost.org/users/ news/version_1.62.0 You can also download directly from SourceForge: http://sourceforge.net/ projects/boost/files/boost/1.62.0/ The SHA256 checksums are as follows: b91c2cda8bee73ea613130e19e72c9589e9ef0357c4c5cc5f7523de82cce11f7 boost_1_62_0.7z 36c96b0f6155c98404091d8ceb48319a28279ca0333fba1ad8611eb90afb2ca0 boost_1_62_0.tar.bz2 440a59f8bc4023dbe6285c9998b0f7fa288468b889746b1ef00e8b36c559dce1 boost_1_62_0.tar.gz 084b2e0638bbe0975a9e43e21bc9ceae33ef11377aecab3268a57cf41e405d4e boost_1_62_0.zip Tom Kent has made pre-built windows binaries, and they are available at: https://sourceforge.net/projects/boost/files/boost-binaries/1.62.0/ To install this release on your system, see http://www.boost.org/doc/libs/ release/more/getting_started/index.html Thanks, --The Boost release team

6 5

[release] Master open for changes.
by Rene Rivera 30 Sep '16

30 Sep '16

FYI.. Master branches are now open for changes for the next release. Note that because of the late 1.62.0 release the window for the next release is shorter than usual. And there is now less than a month before master closes again for new libraries. Please consult the calendar for further dates. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

1 0

[asio] inefficiency in the polling
by Tatsuyuki Ishi 29 Sep '16

29 Sep '16

The current run/poll_one does polling regardless if there's task in the queue. If there's task in the queue, polling is just a waste of system call, since there's already a job to do. Also, my common use case is "wait and consume all work", which is not covered efficiently by current design. (run_one+poll takes two system calls) Side note: on Windows asio performs even worse, it only retrieve one event per syscall... Not sure if it's intended. Friendly note: please use "Reply to All" when replying to me.

4 3

Population count procedure in dynamic_set
by Wojciech Muła 28 Sep '16

28 Sep '16

Hello! The library dynamic_bitset contains a slow population count procedure: https://github.com/boostorg/dynamic_bitset/blob/340822f979371973fe4a8436362… There are several better, faster and (more or less) portable algorithms. Daniel Lemire, Nathan Kurz and I work on a library which provides fastest possible implementations for CPU having AVX2 instruction set, you can check out its current state: https://github.com/CountOnes/hamming_weight. I also did an extensive comparison of different algorithms on different machines: https://github.com/WojciechMula/sse-popcount, one example https://github.com/WojciechMula/sse-popcount/blob/master/results/skylake/sk… As I mentioned these algorithms are different, the fastest use SIMD instructions, other depends on a CPU instruction. However, some approaches are portable, machine-independent, like this https://github.com/WojciechMula/sse-popcount/blob/master/popcnt-bit-paralle… It's possible to provide better solution at small cost, a lot of work has already been done. Would you be interested in including such boosted procedures as part of dynamic_bitset (or a new library)? Popcount itself is used in number of fields: I've found it in DNA matching (Jaccard index), computer vision, databases, and Daniel recently reported application in machine learning. best regards Wojciech

2 1

[container] Trie data structure
by Зайцев Александр 28 Sep '16

28 Sep '16

Hi! My implementation of Aho-Corasick uses my own implementation of trie data structure. But i want something to use from Boost. Is there trie in Boost? If not, can I start work on trie for Boost? -- Best regards, Alexander Zaitsev

6 9

Re: [boost] [Boost-users] [release] Boost 1.62.0 Release Candidate 1
by Marshall Clow 28 Sep '16

28 Sep '16

On Tue, Sep 27, 2016 at 7:14 PM, Edward Diener <eldiener(a)tropicsoft.com> wrote: > On 9/27/2016 9:24 PM, Marshall Clow wrote: > >> >> >> On Mon, Sep 26, 2016 at 5:52 PM, Marshall Clow <mclow.lists(a)gmail.com >> <mailto:mclow.lists@gmail.com>> wrote: >> >> On Mon, Sep 26, 2016 at 7:36 AM, Rene Rivera <grafikrobot(a)gmail.com >> <mailto:grafikrobot@gmail.com>> wrote: >> >> The release candidates for the 1.62.0 release are now available >> at: >> >> >> [snip] >> >> >> >> Now to run some tests.... >> >> -- Marshall >> >> >> The test "vmd/test/test_doc_modifiers_return_type.cpp" hangs clang. >> Reported as https://llvm.org/bugs/show_bug.cgi?id=30546 >> > > Evidently clang runs out of memory. Note that with VC++ and gcc the test > passes. > > I don't know why clang would run out ot memory while VC++ and gcc do not > but I have not queried the clang mailing list further about it. An educated > guess is that clang calculates some fixed size for the preprocessor and > when macro expansions cause that fixed size to overrun you get an out of > memory condition. I can hardly believe that the preprocessor is really > running out of virtual memory, no matter how complicated the preprocessor > code gets in VMD. > > When I was discussing the problem with Richard, he opined that that might be a problem, if the preprocessed source exceeded 1 GB in size - which it doesn't. (GCC expands this test to about 700K) So I suspect it is "just a bug" -- Marshall

1 0

[release] Boost 1.62.0 Release Candidate 1
by Rene Rivera 28 Sep '16

28 Sep '16

The release candidates for the 1.62.0 release are now available at: https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… https://sourceforge.net/projects/boost/files/boost/1.62.0.rc.1/boost_1_62_0… The SHA256 checksums are as follows: b91c2cda8bee73ea613130e19e72c9589e9ef0357c4c5cc5f7523de82cce11f7 boost_1_62_0_rc1.7z 36c96b0f6155c98404091d8ceb48319a28279ca0333fba1ad8611eb90afb2ca0 boost_1_62_0_rc1.tar.bz2 440a59f8bc4023dbe6285c9998b0f7fa288468b889746b1ef00e8b36c559dce1 boost_1_62_0_rc1.tar.gz 084b2e0638bbe0975a9e43e21bc9ceae33ef11377aecab3268a57cf41e405d4e boost_1_62_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. Thanks, the release managers. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

6 9

[dll] Problem building documentation on Windows
by Vinnie Falco 27 Sep '16

27 Sep '16

I am trying to build the Boost documentation on Windows and I am encountering this error bash-4.3$ pwd /d/lib/boost_1_62_0/libs/dll/doc bash-4.3$ bjam Jamfile.v2:66: in modules.load *** argument error * rule doxygen ( target : sources + : requirements * : default-build * : usage-requirements * ) * called with: ( autodoc_shared_library_core : : <doxygen:param>HIDE_UNDOC_MEMBERS=YES <doxygen:param>HIDE_UNDOC_CLASSES=YES <doxygen:param>HIDE_SCOPE_NAMES=YES <doxygen:param>EXTRACT_ALL=NO <doxygen:param>EXTRACT_PRIVATE=NO <doxygen:param>BUILTIN_STL_SUPPORT=YES <doxygen:param>ENABLE_PREPROCESSING=YES <doxygen:param>MACRO_EXPANSION=YES <doxygen:param>ALIASES= \ "forcedlink{1}=\xmlonly<link linkend='boost.dll.\1'>boost::dll::\1</link>\endxmlonly" \ "forcedmacrolink{1}=\xmlonly<link linkend='\1'>\1</link>\endxmlonly" <doxygen:param>PREDEFINED= \ "BOOST_RV_REF(T)=T&&" \ "BOOST_RV_REF(shared_library)=shared_library&&" \ "BOOST_COPY_ASSIGN_REF(shared_library)=const shared_library&" \ "BOOST_MOVABLE_BUT_NOT_COPYABLE(shared_library)= \ shared_library(const shared_library&) = delete; \ shared_library& operator=(const shared_library&) = delete; " \ "BOOST_DLL_IMPORT_RESULT_TYPE=result_type" \ "BOOST_DLL_MANGLED_IMPORT_RESULT_TYPE=result_type" \ "BOOST_EXPLICIT_OPERATOR_BOOL()=explicit operator bool() const noexcept;" \ "BOOST_DLL_DOXYGEN" <xsl:param>boost.doxygen.reftitle=Shared Library Reference ) * missing argument sources D:/lib/boost_1_62_0/tools/build/src/tools\doxygen.jam:622:see definition of rule 'doxygen' being called D:/lib/boost_1_62_0/tools/build/src/build\project.jam:325: in load-jamfile D:/lib/boost_1_62_0/tools/build/src/build\project.jam:64: in load D:/lib/boost_1_62_0/tools/build/src/build\project.jam:145: in project.find D:/lib/boost_1_62_0/tools/build/src\build-system.jam:535: in load D:\lib\boost_1_62_0\tools\build\src/kernel\modules.jam:295: in import D:\lib\boost_1_62_0\tools\build\src/kernel/bootstrap.jam:139: in boost-build D:\lib\boost_1_62_0\boost-build.jam:17: in module scope I get the same error when I try to build the full documentation from boost_1_62_0/doc/ My doxygen is at version 1.8.12 -- Follow me on Github: https://github.com/vinniefalco

2 5

[fiber] design fault with multithreading
by Tatsuyuki Ishi 27 Sep '16

27 Sep '16

The current design doesn't allow a work-stealing algorithm to distribute work perfectly. Unfortunately, the use of sleep queue and remote ready queue made it insufficient for schedulers like shared_work. Instead here, I'd like to propose it as non-pure virtual function in the algorithm class. This allows schedulers to override the queues, and enables the use of underlying implementation's timer manager, which is included in Asio. Friendly notice: please use "Reply All" when replying to me.

1 0

Boost should not be saying "_FPOSOFF"
by Billy O'Neal (VC LIBS) 27 Sep '16

27 Sep '16

Hello, Boost folks. :) I tried to remove this undocumented internal macro from our STL because we used it in only one place, but this broke Boost: #define _FPOSOFF(fp) ((long long)(fp)) ...patience... ...found 722 targets... ...updating 18 targets... common.mkdir build\boost\bin.v2\libs common.mkdir build\boost\bin.v2\libs\iostreams common.mkdir build\boost\bin.v2\libs\iostreams\build common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99 common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\debug common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\file_descriptor.obj file_descriptor.cpp d:\src\vc\wcfb01\qa\vc\FE\3rdpartycomp\boost_1_60_0\boost/iostreams/positioning.hpp(107): error C3861: '_FPOSOFF': identifier not found libs\iostreams\src\file_descriptor.cpp(265): warning C4244: 'argument': conversion from 'std::streamsize' to 'DWORD', possible loss of data libs\iostreams\src\file_descriptor.cpp(289): warning C4244: 'argument': conversion from 'std::streamsize' to 'DWORD', possible loss of data cl /Zm800 -nologo @"build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\file_descriptor.obj.rsp" ...failed compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\file_descriptor.obj... compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\mapped_file.obj mapped_file.cpp d:\src\vc\wcfb01\qa\vc\FE\3rdpartycomp\boost_1_60_0\boost/iostreams/positioning.hpp(107): error C3861: '_FPOSOFF': identifier not found libs\iostreams\src\mapped_file.cpp(59): warning C4244: 'return': conversion from 'const boost::iostreams::stream_offset' to '::size_t', possible loss of data libs\iostreams\src\mapped_file.cpp(325): warning C4244: 'argument': conversion from 'boost::iostreams::stream_offset' to 'SIZE_T', possible loss of data cl /Zm800 -nologo @"build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\mapped_file.obj.rsp" ...failed compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi\mapped_file.obj... ...skipped <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi>libboost_iostreams-vc-mt-gd-1_60.lib for lack of <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi>file_descriptor.obj... ...skipped <pstage\lib>libboost_iostreams-vc-mt-gd-1_60.lib for lack of <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\debug\link-static\threading-multi>libboost_iostreams-vc-mt-gd-1_60.lib... common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\release common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static common.mkdir build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\file_descriptor.obj file_descriptor.cpp .\boost/iostreams/positioning.hpp(107): error C3861: '_FPOSOFF': identifier not found libs\iostreams\src\file_descriptor.cpp(265): warning C4244: 'argument': conversion from 'std::streamsize' to 'DWORD', possible loss of data libs\iostreams\src\file_descriptor.cpp(289): warning C4244: 'argument': conversion from 'std::streamsize' to 'DWORD', possible loss of data cl /Zm800 -nologo @"build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\file_descriptor.obj.rsp" ...failed compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\file_descriptor.obj... compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\mapped_file.obj mapped_file.cpp .\boost/iostreams/positioning.hpp(107): error C3861: '_FPOSOFF': identifier not found libs\iostreams\src\mapped_file.cpp(59): warning C4244: 'return': conversion from 'const boost::iostreams::stream_offset' to '::size_t', possible loss of data libs\iostreams\src\mapped_file.cpp(325): warning C4244: 'argument': conversion from 'boost::iostreams::stream_offset' to 'SIZE_T', possible loss of data cl /Zm800 -nologo @"build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\mapped_file.obj.rsp" ...failed compile-c-c++ build\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi\mapped_file.obj... ...skipped <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi>libboost_iostreams-vc-mt-1_60.lib for lack of <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi>file_descriptor.obj... ...skipped <pstage\lib>libboost_iostreams-vc-mt-1_60.lib for lack of <pbuild\boost\bin.v2\libs\iostreams\build\msvc-99\release\link-static\threading-multi>libboost_iostreams-vc-mt-1_60.lib... ...failed updating 4 targets... ...skipped 4 targets... ...updated 10 targets... failed Billy3

8 18

[iterator] Is there any interest in Null Iterator Adaptor ?
by Rahman Salim Zengin 27 Sep '16

27 Sep '16

Hi! It would be pleasure for me to hear about your precious thoughts. https://github.com/rszengin/null_iterator Best regards.

3 5

Re: [boost] [fiber] Suggestions regarding asio
by Tatsuyuki Ishi 27 Sep '16

27 Sep '16

It would be better if you used "Reply to All", since I disabled the delivery from the list. > When considering using multiple threads with an io_service passed to a custom Boost.Fiber scheduler, I keep bumping into the problem that a given fiber scheduler instance must always run on its original thread -- but I know of no way to give an Asio handler "thread affinity." How do we get processor cycles to the scheduler on the thread whose fibers it is managing? Since we only poll on one master thread, we can easily get affinity. Maybe pseudocode is easier: * We have two class, one for main polling, others waiting for job. * The first one, polls from asio using the same way as the example (poll, or run_one). while(true) { if(!run_one()) stop_other_threads(); // No more work in asio, give up waiting poll(); // flush the queue // Now we should have some fibers in the queue. yield(); // continue execution } * Other threads, uses condvar to wait on the ready queue. awakened(){queue.push_back(f); cv.notify_[one,all](); iosvc.post([]{});} pick_next(){while(!jobs_available){cv.wait();} return job;}

5 7

Code complexity
by Vard Antinyan 27 Sep '16

27 Sep '16

Dear Boost developers, We have undertaken a task to assess code complexity triggers and generate recommendations for developing simple and understandable code. Our intension is to share the results with you, developers, so everyone can learn the triggers behind complex software. We need your help for rigorous results. My request to you is - if you get 5-10 min. time, would you please consider to answer the questions of this survey on code complexity? https://goo.gl/forms/h9WXZ8VSEw7BUyHg1 You are welcome to learn preliminary results through this link: https://www.facebook.com/SoftwareCodeQuality/photos/?tab=album&album_id=163… The results will be shared in a public webpage and everyone possible will be invited to learn and discuss them. Your knowledge and experience is vital for achieving substantial and generalizable results, and your effort is much appreciated! Sincerely Vard Antinyan PhD candidate in University of Gothenburg, Sweden Tel: 0046317725707

2 1

(Boost) Synapse update
by Emil Dotchevski 27 Sep '16

27 Sep '16

(Synapse is not part of Boost. I appreciate feedback as well as looking for someone willing to volunteer as review manager when Synapse is submitted for formal review.) Synapse is a signal-programming library similar to the Qt signal/slot system and Boost Signals 2. The difference is that Synapse is non-intrusive: any object of any static type whatsoever can serve as an emitter. I've just updated Synapse with support for interthread communication. It is available on github: http://zajo.github.io/boost-synapse/index.html. Thanks, Emil

3 5

Need help with errors while building boost for clang on android NDK
by Robert Dailey 26 Sep '16

26 Sep '16

I'm using NDK r11 and I'm setting up project-config.jam to build boost using clang + llvm STL. I'm running into a few errors that I do not know how to solve. I will post my config file at the bottom. First problem is that boost does not know where to find tools 'ar' and 'ranlib': clang-linux.archive bin.v2\libs\container\build\clang-linux-android\release\link-static\runtime-link-static\target-os-linux\threading-multi\libboost_container-clang-mt-s-1_61.a '"ar"' is not recognized as an internal or external command, operable program or batch file. '"ranlib"' is not recognized as an internal or external command, operable program or batch file. How can I explicitly specify the NDK path to these executables? Second problem is related to some assembler stuff, I think. I get these errors while compiling boost thread: clang-linux.compile.asm bin.v2\libs\context\build\clang-linux-android\release\link-static\runtime-link-static\target-os-linux\threading-multi\asm\make_i386_ms_pe_gas.o libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:30:1: error: unknown directive .def _make_fcontext; .scl 2; .type 32; .endef ^ libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:30:22: error: unknown directive .def _make_fcontext; .scl 2; .type 32; .endef ^ libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:30:36: error: expected identifier in directive .def _make_fcontext; .scl 2; .type 32; .endef ^ libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:30:40: error: unknown directive .def _make_fcontext; .scl 2; .type 32; .endef ^ libs\\context\\src\\asm\\make_i386_ms_pe_gas.asm:136:1: error: unknown directive .def __exit; .scl 2; .type 32; .endef ^ How can I solve this? I have no idea at this point. I'm invoking the build using: b2 --without-python threading=multi link=static runtime-link=static toolset=gcc-android target-os=linux threadapi=pthread --stagedir=android stage And my project-config.jam looks like: import option ; option.set keep-going : false ; androidNDKRoot = E:/android/ndk ; androidAbiVer = 4.9 ; androidPlatform = windows-x86_64 ; using clang : android : $(androidNDKRoot)/toolchains/llvm/prebuilt/$(androidPlatform)/bin/clang++ : <compileflags>--sysroot=$(androidNDKRoot)/platforms/android-15/arch-arm <compileflags>-Os <compileflags>-fno-strict-aliasing <compileflags>-O2 <compileflags>-DNDEBUG <compileflags>-g <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++abi/libcxxabi/include <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++/libcxx/include <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/llvm-libc++/libs/armeabi-v7a <compileflags>-I$(androidNDKRoot)/sources/android/support/include <compileflags>-DANDROID <compileflags>-D__ANDROID__ <compileflags>-D__arm__ <compileflags>-D_REENTRANT ;

1 1

[Math/Special Functions] Is there any interest in the Lambert W function?
by Balázs Cziráki 26 Sep '16

26 Sep '16

Greetings! I'm working on a C++ implementation of the Lambert W (a.k.a. product logarithm or Omega function) and I wanted to ask the Boost developer community if there is interest in adding it to the library. The current version can be found on GitHub: https://github.com/CzB404/lambert_w/ I've successfully tested it with Cygwin GCC v5.4, v6.2 and with MinGW GCC that is supplied with Code::Blocks, and also on Visual Studio 2015. A test on a Linux based OS (probably Ubuntu) is also going to happen. Any suggestions or constructive criticism is welcome. Best regards, Balázs Cziráki

4 5

[range] sub_range of istream_range
by Andrew Hundt 26 Sep '16

26 Sep '16

I’m trying to iterate through a file using sub_ranges of an istream_range of an ifstream. However, it seems if I construct sub ranges of various subsets of the full istream_range, try to adjust the limits with advance_begin and advance_end, and then access them I get null dereferences. Any thoughts? I can produce an example if needed. Cheers! Andrew Hundt

1 0

markable -- informal review request
by Andrzej Krzemienski 24 Sep '16

24 Sep '16

Hi Everyone, I would like to ask your opinion, suggestions, and perhaps an informal review of the 'markable' library. An alternative to boost::optional when performance really matters. It is the second incarnation of the 'compact_optional' library that I have presented last year. The main differences from the previous version: * name change: it is called 'markable' so that it is not confused with 'optional'. It uses "mark values" and mark policies" * it has the ability to mark an empty state even for the types with strong invariants, by marking a bit pattern rather than any proper value of T (an idea by Matt Calabrese) An example use case: typedef markable<mark_int<int, -1>> opt_int; opt_int oi; opt_int o2 (2); assert (!oi.has_value());assert (o2.has_value());assert (o2.value() == 2); static_assert (sizeof(opt_int) == sizeof(int), ""); The github repository: https://github.com/akrzemi1/markable And documentation therein: https://github.com/akrzemi1/markable/tree/master/documentation Any comments, suggestions or critique are most welcome. Regards, &rzej;

4 8

[fiber] Suggestions regarding asio
by Tatsuyuki Ishi 22 Sep '16

22 Sep '16

The current example seems non-flexible and very hacky. 1. The timer handler has no problem, since it's expected to be called from any thread. (Description in "Deeper Dive into asio" is meaningless) 2. Possible alternatives: * A post(empty lambda) is a little bit waste but solves the threading problem. It wakes up one thread by doing interrupt of epoll etc. Maybe adding a interrupt method to asio codebase could be more efficient. * One thread doing event polling and the other doing condvar is enough. Since we're not expecting a slow handler (most times, it just make a fiber ready), this should be sufficient. Correct me if I'm wrong.

2 1

[interprocess] Improved shared_memory lifetime using file locks?
by Sebastian Theophil 21 Sep '16

21 Sep '16

Hi, coming from Windows, the filesystem persistence of basic_managed_shared_memory is giving us headaches. When we have N processes accessing the same shared memory, and one of them crashes, the other N-1 are in an undefined state. That’s the same on Windows and POSIX platforms and is ok for us. On Windows, the problem resolves itself when the other N-1 processes are all closed and then restarted, because Windows deletes the shared memory automatically. On POSIX systems, I think we can use file locks to make sure that the shared memory is reinitialized by the first process to access it. I’d appreciate any feedback, especially if it points out the problems with this approach: - basic_managed_shared_memory(boost::interprocess::open_or_create, …) opens the backing file with flags O_CREAT | O_EXLOCK | O_NONBLOCK - if that succeeds: - we are the first - (re-) initialize shared memory - also a good time to unlink/open the named POSIX semaphore that’s hanging around in an invalid state too! - degrade exclusive lock using flock(LOCK_SH) - else - open file with flag O_SHLOCK (open only, and blocking!) - when that succeeds, open shared memory Problems I can see: - Only works when (advisory) shared and exclusive locking and the degradation of one to the other is supported (at least flock not supported on Windows, e.g.) - What about other file systems? NFS? - Somebody could lock all your files. (OTOH, sb could also delete all my backing files all the time. My application would run, but not have any shared memory. Might be an advantage that my application does *not* run when the file is locked.) - What else? Is this worth implementing in boost.interprocess? I appreciate any feedback, Sebastian PS: I’ve googled previous discussions about shared memory lifetime in boost.interprocess. I don’t claim that my proposal gives the same semantics as Windows shared memory. It doesn’t and it seems impossible to achieve. I’m looking for, erm, usable semantics on POSIX systems. Clearly, everybody has to implement some lifetime tracking. It would be nice if boost.interprocess provided one or more solutions. -- Dr. Sebastian Theophil | stheophil(a)think-cell.com Senior Software Engineer We are looking for C++ Developers: https://www.think-cell.com/career think-cell Software GmbH | Chausseestr. 8/E | 10115 Berlin | Germany https://www.think-cell.com | phone +49 30 666473-10 | US phone +1 800 891 8091 Amtsgericht Berlin-Charlottenburg, HRB 180042 Directors: Dr. Markus Hannebauer, Dr. Arno Schödl

1 0

[release] 1.62.0 Master branch is closed
by Rene Rivera 21 Sep '16

21 Sep '16

The master branch is now closed for all changes, except by permission from a release manager. Thanks, The Release Team -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

1 0

[release] Boost 1.62.0. Beta 2
by Rene Rivera 20 Sep '16

20 Sep '16

The packages for 1.62.0 beta 2 are now available: <https://sourceforge.net/projects/boost/files/boost/1.62.0.beta.2/> The SHA256 checksums are as follows: 95feae3620b3e604e93f14d97195fc04a4b67063692859af8df19657d41b82d5 boost_1_62_0_b2.7z 27bc9b328ff73d7dbf80cd9d4b5f79b0878221e5d8e4b6c47444b135edc1080a boost_1_62_0_b2.tar.bz2 3939d5efa683449e87b374d7e92e3eeb6490063ddb2877919f0fad26e3a0f53e boost_1_62_0_b2.tar.gz cff9ab5db0928244c4c836cf3da5140e6e93db7756e2791ba99a21104ad3aa72 boost_1_62_0_b2.zip As always, the release managers would appreciate it if you download the archive of your choice and give building and using it a try. Please report both success and failure, and anything else that is noteworthy. Thanks! -- The release managers -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

4 9

Re: [boost] first steps to submitting - boost :: observers
by Bjorn Reese 19 Sep '16

19 Sep '16

On 09/17/2016 08:10 PM, Robert McInnis wrote: > https://github.com/tiny/boost_observers.git What are the advantages of this library over Boost.Signals2 [1]? Same question with regards to the Boost.Synapse [2] proposal. My impression from a brief look at your repository is that you need to focus more on thread-safety. Is there any way to avoid the overhead of thread synchronization in a single-threaded application? Observers are invoked while the mutex is locked, so observers cannot make calls on the subject. How does the lock-free mutex perform, especially when congested? Why is the lock-free mutex recursive? There are several member variables that are used as if they are atomic but they are not declared as such, e.g. Subject::_block, Numeric<T>::_x (think T == long long.) The Scope template can be replaced by lock_guard if you model the LockFreeMutex after the BasicLockable concept [3]. The thread_self() and thread_pid() functions can be replaced by this_thread::get_id(). Replace the hAtomic macro with a type alias. Use <cstdint> instead of <stdint.h> to reduce polution of the global namespace. [1] http://www.boost.org/doc/html/signals2.html [2] http://zajo.github.io/boost-synapse/ [3] http://en.cppreference.com/w/cpp/concept/BasicLockable

4 6

[density] version 7
by Giuseppe Campana 19 Sep '16

19 Sep '16

Hi to all, I’ve just merged to the master branch a major review of density, an header-only library of heterogeneous dense containers. Unfortunately this update includes some renamings. Anyway the new names are simpler and more explicative: heterogeneous_array, heterogeneous_queue, function_queue, lifo_array. The update consists of fixes and optimizations. The results of the benchmarks are included in the documentation. The container function_queue gives the best results, being many times faster than an std::queue of std::function’s (http://peggysansonetti.it/tech/density/html/func_queue_bench.html) The library is not yet ready for asking a formal review, but hopefully it will be in a few months. Html overview (now a little more schematic) and reference doc at http://peggysansonetti.it/tech/density/html/index.html Repository at https://github.com/giucamp/density/tree/master Giuseppe Campana.

1 0

Fuzzy string search to the Boost String Algortihm
by Зайцев Александр 19 Sep '16

19 Sep '16

Hello. I want to discuss about some proposals. I am working on Levenshtein distance and Damerau-Levenshtein distance algortihms. I hope, that these implementations will be pulled to the Boost String library. But i think that we can add to the Boost String Library some more algorithms for fuzzy searhing. I mean these algortihms: Levenshtein distance Damerau-Levenshtein distance Bitap algorithm with modifications by Wu and Manber Spell-checker method N-gram method Signature hashing method BK-trees What do you think about this idea? If you think that it can be implemented to the Boost String Algo, i will start work on this list immediately. Best regards, Zaitsev Alexander.

2 2

first steps to submitting - boost :: observers
by Robert McInnis 19 Sep '16

19 Sep '16

G'afternoon, This is my first time submitting to a public repo, please be gentle I'd like to submit a series of classes I have been using since '90. The initial set implements a thread safe subject/observer pattern. I have included a handful of example programs, two fairly trivial and the third more in-depth. All examples are single file examples to make compilation trivial. This is the first re-work of my original tools, making them more boost-friendly. I expect to add more default observer templates and observable objects, but that will come with time. WHY? -- The reason for these classes is to help insure the mathematical integrity of your data model in relation to your business rules. If at any time you were to change one of your data elements without updating all those dependent on it, then your data integrity would be compromised. These classes look to solve that. As an example: -- using namespace boost::observers ; Numeric<long> x, y, z ; // rules: y = x + 2; z = y * 3 ; x = 5 ; printf( "%d \n", z ) ; x = 1 ; printf( "%d \n", z ) ; -- Setting the rules properly, the classes allow for 'z' to be correct each time it's printed using code almost exactly like this. This will remove the possibility of accidently forgetting to trigger the rule update. WHERE? -- The repo can be found here: git clone https://github.com/tiny/boost_observers.git Any input on how to continue from this point would also be much appreciated. I have skype and ventrilo servers available if that helps. Thanks in advance, Rob -- Robert McInnis

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[release] Boost 1.62.0 - One week to close.
by Rene Rivera 16 Sep '16

16 Sep '16

Reminder.. Next week, on the 21st, the release will close for all changes. Except for extra ordinary and approved changes. Please exercise caution when merging changes to master branches. Remember that changes need to be well tested on the develop branches before going into master. And that changes at this point should be for critical problems. Thanks, the Release Team. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 2

[uuid] PR to remove auto-linking to advapi32 when BOOST_ALL_NO_LIB is defined
by Edward Diener 15 Sep '16

15 Sep '16

I don't know how to resolve a PR for uuid ( https://github.com/boostorg/uuid/pull/11 ). If a library exists only as a DLL and not as a static library should BOOST_ALL_NO_LIB still be considered in effect ? My viewpoint is 'no' but the person who created the PR believes that the BOOST_ALL_NO_LIB config macro should turn off any #pragma auto-linking in code even when their is no other way to use a library other than as a shared library. What I am afraid of is breaking user code even if BOOST_ALL_NO_LIB is defined by producing link errors. But perhaps I am wrong and this should be considered justified when BOOST_ALL_NO_LIB is being used.

5 7

[algorithm] Musser-Nishanov sequence search algorithm
by Jeremy Murphy 15 Sep '16

15 Sep '16

Dear Boost community, most of you are probably familiar with Dave Musser, well known for his work on generic programming, introsort and more. What you maybe didn't know, and I didn't until not that long ago, is that he and Gor Nishanov also designed (based off KMP) and wrote a generic sequence search algorithm to compete with Boyer-Moore, etc, which apart from being competitively fast is ostensibly more generic than the others. You can read for yourself on Dave Musser's website: http://www.cs.rpi.edu/~musser/gp/algorithms.html By "more generic" I mean it has a fallback algorithm if the corpus does not have random-access iterators, and its behaviour can easily be tuned for the alphabet size to dramatic effect. (I haven't looked into the 'tunability' of BM, BMH, KMP, etc, so I'm not sure if this is a unique feature.) But at face value, it appears to have powerful features that the others lack without compromising performance, which is pretty neat. So I've been in contact with the original authors and with their permission am just playing the messenger to bring the algorithm to wider attention with the expectation that it is something we could really benefit from. What I hope for now is to have discussion on whether indeed it is an algorithm that we want, presumably alongside the others in Boost.Algorithm. My slightly more controversial thought is that, if no shortcomings or weaknesses are revealed, this could up being the superior search algorithm. I've opened a pull request on Boost.Algorithm with the code so everyone can play around with it if they want. https://github.com/boostorg/algorithm/pull/25 Looking forward to hearing what everyone thinks. Cheers. Jeremy

1 0

[uuid][rational] Pushed bug fixes to 'master'
by Edward Diener 15 Sep '16

15 Sep '16

I pushed some bug fixes from 'develop' to 'master' for the uuid and rational libraries. The fixes had been tested on the 'develop' branch for a long time and the results showed that the fixes were fine. While none of the fixes were major I felt that the fixes were important enough to go in the upcoming Boost release if they are going to be picked up. I, and probably other members of CMT, should have been more proactive in pushing these fixes to 'master' sooner, once they showed green on the develop test matrix.

2 3

Final Call for Extended Abstracts and Posters: International Conference on Information Society (i-Society 2016), Technical Co-Sponsored by IEEE UK/RI Chapter!
by David Brown, i-Society 2016 14 Sep '16

14 Sep '16

1 0

[log] Boost 1.62 cannot compile log with Oracle Developer Studio 12.5
by Aparna Kumta 14 Sep '16

14 Sep '16

Compiling Boost.log with Oracle Developer Studio 12.5, we see the following failure: % "CC" -std=c++11 -library=stdcpp,CrunG3 -xO4 -mt -erroff=%none -m32 -KPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_DATE_TIME_DYN_LINK=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_LOG_BUILDING_THE_LIB=1 -DBOOST_LOG_DLL -DBOOST_LOG_HAS_PTHREAD_MUTEX_ROBUST -DBOOST_LOG_WITHOUT_DEBUG_OUTPUT -DBOOST_LOG_WITHOUT_EVENT_LOG -DBOOST_SPIRIT_USE_PHOENIX_V3=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_DONT_USE_CHRONO=1 -DBOOST_THREAD_POSIX -DBOOST_THREAD_USE_DLL=1 -DDATE_TIME_INLINE -DNDEBUG -D_XOPEN_SOURCE=500 -D__EXTENSIONS__ -D__STDC_CONSTANT_MACROS -D__typeof__=__typeof__ -I"../../.." -I"../../../libs/log/src" -c -o "../../../bin.v2/libs/log/build/sun/release/stdlib-gnu/threading-multi/posix/ipc_reliable_message_queue.o" "../../../libs/log/src/posix/ipc_reliable_message_queue.cpp" "../../../libs/log/src/posix/ipc_reliable_message_queue.cpp", line 61: Error: #error Boost.Log: Native 32-bit atomic operations are required but not supported by Boost.Atomic on the target platform. This seems to be a configuration issue. The following changes seems to work: 1) In boost/atomic/detail/platform/platform.hpp % !diff diff ./platform.hpp ./platform.hpp_orig 46c46 < #elif (defined(__GNUC__) || (__SUNPRO_CC >= 0x5130)) && (defined(__i386__) || defined(__x86_64__)) --- > #elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) 68c68 < #elif (defined(__GNUC__) || (__SUNPRO_CC >= 0x5130)) && defined(__sparc) --- > #elif defined(__GNUC__) && defined(__sparc_v9__) The above change causes the compilation to proceed further, however, it fails again with another configuration issue causing failure to build atomic library "CC" -std=c++11 -library=stdcpp,CrunG3 -xO4 -mt -erroff=%none -m32 -KPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_ATOMIC_SOURCE -DNDEBUG -I"../../.." -c -o "../../../bin.v2/libs/atomic/build/sun/release/stdlib-gnu/threading-multi/lockpool.o" "../../../libs/atomic/src/lockpool.cpp" "../../../boost/atomic/detail/ops_gcc_sparc.hpp", line 69: Error: The function "fence_before_store" must have a prototype. In boost/atomic/detail/ops_gcc_sparc.hpp, the following change seems to resolve the issue % !diff % diff ./ops_gcc_sparc.hpp ./ops_gcc_sparc.hpp_orig 69c69 < fence_before(order); --- > fence_before_store(order); 71c71 < fence_after(order); --- > fence_after_store(order); 110c110 < fence_before(order); --- > base_type::fence_before(order); 118c118 < fence_after(order); --- > base_type::fence_after(order); I will submit a PR for this change. Thanks, Aparna

1 0

[filesystem] How to remove specific files from a directory?
by Andrzej Krzemienski 14 Sep '16

14 Sep '16

Hi, I wonder what is boost::filesystem recommendation for solving the following problem. I want to remove all files from a given directory that satisfy a certain predicate, e.g., only these whose names start with letter "s". It is my understanding that the calling filesystem::remove may invalidate the iterator, and therefore the following solution is incorrect: fsys::directory_iterator it{path}, itEnd{}; for ( ; it != itEnd ; ++it ) { if (predicate(*it)) fsys::remove(it->path()); } But, is the following guaranteed to work?: fsys::directory_iterator it{path}, itEnd{}; for ( ; it != itEnd ; ) { if (predicate(*it)) fsys::remove((it++)->path()); else ++it; } If not, does there exist a dedicated solution for solving this problem that would not require of me N traversals through the directory? Thanks, &rzej;

6 11

[release] Boost 1.62.0 Beta 1
by Rene Rivera 14 Sep '16

14 Sep '16

The first beta packages for 1.62.0 beta 1 are now available: <https://sourceforge.net/projects/boost/files/boost/1.61.0.beta.1/> The SHA256 checksums are as follows: f7cc83e6a3b03cd7aa8822992aa3e36422cc2214644d69277ef55a4db51f44bd boost_1_62_0_b1.7z 4057993811e40b1fd4719675e44c2550b6c2379546192da2299c17fec9a3dddf boost_1_62_0_b1.tar.bz2 fb0c10b625c5ec47cc837b54740540e400c59571b2eabf427c00f32bffc6ca70 boost_1_62_0_b1.tar.gz b38ef21c43c5ff814a2144bc23871c134164e7f51c71672d0f49a44636fb50b5 boost_1_62_0_b1.zip As always, the release managers would appreciate it if you download the archive of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. Thanks! -- The release managers -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

4 4

Re: [boost] [Boost-users] [release] Boost 1.62.0 Beta 1
by Rene Rivera 13 Sep '16

13 Sep '16

On Mon, Sep 12, 2016 at 12:44 AM, Oliver Kowalke <oliver.kowalke(a)gmail.com> wrote: > 2016-09-12 0:00 GMT+02:00 Tom Kent <lists(a)teeks99.com>: > >> Since the fiber build was a failure, >> > > should be fixed > Could someone try a build of the master snapshot to see if it's really fixed? I'm still in favor of a beta 2 build to make sure that gets flushed out >> before going to RCs. >> > > +1 > We can certainly do that. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 1

[math] Undefined reference to promote_args
by Florian Lindner 13 Sep '16

13 Sep '16

Hello, when compiling a file that uses float_distance from #include <boost/math/special_functions/relative_difference.hpp> I get a linking error: undefined reference to `boost::math::tools::promote_args<double, double, float, float, float, float>::type boost::math::float_distance<double, double>(double const&, double const&)' I try to add all boost_math libs I could find, but none helped: -lboost_system -lboost_filesystem -lboost_math_tr1 -lboost_math_c99 -lboost_math_c99 Since float_distance is not a C99 / TR1 function, shouldn't boost.math work as header only? What is the problem here? Thanks, Florian

2 1

[qi][endian]BOOST_ENDIAN_FORCE_PODNESS is defined in Qi
by Takatoshi Kondo 12 Sep '16

12 Sep '16

Hi, I'm using Boost.Endian with Boost.Qi. It seems that BOOST_ENDIAN_FORCE_PODNESS is defined at boost/spirit/home/support/detail/endian.hpp http://www.boost.org/doc/libs/1_61_0/boost/spirit/home/support/detail/endia… And boost/spirit/include/qi.hpp includes boost/spirit/home/support/detail/endian.hpp According to the Boost.Endian document, endian_buffer's constructors are disappeared by BOOST_ENDIAN_FORCE_PODNESS. http://www.boost.org/doc/libs/1_61_0/libs/endian/doc/buffers.html I'd like to use both endian_buffer's constructors and Boost.Qi. Is there any good way to do that? I don't know much abour Boost.Qi, but defining BOOST_ENDIAN_FORCE_PODNESS in the header file makes big side effects. For my workaround, I changed my include order. Sucessfully compiled http://melpon.org/wandbox/permlink/gSijxeBFJorWpzSd Error ocuured http://melpon.org/wandbox/permlink/FVffqcw8JEKGFXU0 --- Takatoshi Kondo

1 0

[property_tree] arrays in info files ?
by alainm 11 Sep '16

11 Sep '16

Hi, Is there a simple way to specify an array value with the info format, something like arr { 42 "" 43 "" 44 "" } but without the empty strings. thanks

1 0

docca: C++ Documentation XSLT library
by Vinnie Falco 09 Sep '16

09 Sep '16

Hi. When I developed Beast for Boost.Asio (https://github.com/vinniefalco/Beast) I lifted the xsl transforms from Boost.Asio (thanks Chris!) and adapted them. These scripts take the output of Doxygen and transform them into Boost.Book code (or QuickBook code or whatever its called). In other words, it creates a file called reference.qbk. This file is included in the documentation, which gets processed through a Jamfile to produce the HTML documentation that you see here: http://vinniefalco.github.io/beast/index.html This is great, and I am using the same system for my new key/value database engine (https://github.com/vinniefalco/NuDB/) The problem is that now I want to start another project and use the same documentation, but there is a considerable amount of copying going on here. The entire reference.xsl file is copied and placed in the new project: https://github.com/vinniefalco/NuDB/blob/master/doc/reference.xsl This file has to be edited significantly because it has references to project-specific namespaces, prefixes, and various other annoying minutiae. Therefore, I have started a new project called "docca:" https://github.com/vinniefalco/docca This project aims to refactor my variant of Boost.Asio's reference.xsl file so that it can be re-used in other projects. The procedure would be to create your own empty .xsl file, and include docca's xsl file after defining some variables. For example: <?xml version="1.0" encoding="utf-8"?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:variable name="namespace" select="'ripple::'"/> <xsl:include href="../include/docca/doxygen.xsl"/> </xsl:stylesheet> Above is the file you provide, while include/docca/doxygen.xsl is provided by docca (This is very much a work in progress). By this point many of you have fallen asleep, XSLT is a great cure for insomnia. If you're still awake you're probably very excited at the prospects of a turn-key solution for making great looking docs out of Javadoc comments in your C++ headers so I'll move right on to the questions: 1. Is there already a system for doing this? 2. If not, is there any interest in such a system? Is this project worth the effort? 3. Is this approach viable? Or is there a different approach? 4. Are these the right tools for the job? 5. Is there anyone out there who is fairly knowledgeable with XSLT and Boost.Book / QuickBook? Disclaimer: I am by no means an expert at either Boost.Book, Quick.Book, XSLT, or bjam. My only experience with these tools is recently, to put the Beast repository together. -- Follow me on Github: https://github.com/vinniefalco

2 1

Header-only singletons (was Re: [config] RFC PR 82)
by Vinnie Falco 09 Sep '16

09 Sep '16

On Mon, Aug 1, 2016 at 4:13 PM, Vinícius dos Santos Oliveira >...I want my library header only and Boost.System requires the category to > be a single static object and it'll even use address comparison to test if the > categories are the same: > ... > Is it guaranteed the above code will return the same object even if this > code was included in different libraries used by the same program? Sorry for the late reply. This header-only idiom works: inline boost::system::error_category const& my_category() { struct my_error_category : boost::system::error_category { ... }; static my_error_category cat; return cat; } This idiom also works: template<class = void> boost::system::error_category const& my_category() { struct my_error_category : boost::system::error_category { ... }; static my_error_category cat; return cat; } Justification: >From the C++ standard (see https://isocpp.org/std/the-standard) 7.1.6 describes inline functions. It says they must exist in every TU that they are used in, and must be the same in all TUs (no diagnostic required). 7.1.6 p6 also states that the address of an (extern) inline function shall be the same in all TUs. Elsewhere, the standard specifies that inline functions are extern by default. Empirical evidence also supports these claims, both of the aforementioned idioms have been used extensively in my projects under gcc, clang, and msvc. This likely upcoming feature (maybe its already in?) further cements support for global variables in header-only libraries: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4424.pdf However, even in the absence of additional language features, the ability to have global variables in header-only libraries exists today, with nothing more than C++11 support. Hope this helps!

1 0

[config] recent change to suffix.hpp causing several failures for Oracle Developer Studio 12.5
by Aparna Kumta 09 Sep '16

09 Sep '16

A recent change to suffix.hpp seems to cause several tests to fail when compiling with Oracle Developer Studio12.5. The error is: "CC" -std=c++11 -xO4 -mt -erroff=%none -m32 -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_STATIC_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_SYSTEM_STATIC_LINK=1 -DBOOST_TEST_NO_AUTO_LINK=1 -DBOOST_TIMER_STATIC_LINK=1 -DNDEBUG -D__typeof__=__typeof__ -I".." -c -o ./count.o" "../libs/accumulators/test/count.cpp" "../boost/config/suffix.hpp", line 628: Error: Badly formed constant expression. <snipped> See: http://www.boost.org/development/tests/develop/developer/output/oracle-spar… % diff ./suffix.hpp ./suffix.hpp_orig 626a627,630 > # elif defined(__has_cpp_attribute) > # if __has_cpp_attribute(noreturn) > # define BOOST_NORETURN [[noreturn]] > # endif % Thanks, Aparna

2 1

[test] Test failures for gcc 4.6
by Andrey Semashev 09 Sep '16

09 Sep '16

Hi, I'm seeing these test failures for gcc 4.6 (MinGW): http://www.boost.org/development/tests/develop/developer/output/igaztanaga-… Looks like the error originates from Boost.Test, and I can also see lots of failures in Boost.Test itself for that compiler. Is this a known problem? Any fixes planned?

2 5

Gmane going away
by Tom Kent 07 Sep '16

07 Sep '16

So it looks like Gmane is under attack and the guy who runs it is thinking about just turning it off (that would be sad). https://lars.ingebrigtsen.no/2016/07/28/the-end-of-gmane/ Anyway, I know a lot of boost users use is as the gnu mailman archive pages are really hard to use. I would like to propose that we (specifically the list owner(s)) mirror the boost mailing lists to the mail-archive.com site. It has good search features and decent thread browse-ability. Thoughts? Tom

8 9

[release] documentation of 1.62 betaX
by Raffi Enficiaud 06 Sep '16

06 Sep '16

Hi, I cannot see the documentation of any of the libraries from http://www.boost.org/doc/libs/1_62_0_beta1/ . Can anyone please indicate me where I may check the generated online documentation for the betaX/RCX? Thanks, Raffi

2 3

[release] 1.62 Open for fixes.
by Rene Rivera 06 Sep '16

06 Sep '16

Reminder.. The master branch is open for bug fixes, and doc changes, without permission. Any other changes need the permission of a release manager. The release team. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 2

boost.Test: new patch for 11756
by André Draszik 05 Sep '16

05 Sep '16

Hi, I have attached a patch to https://svn.boost.org/trac/boost/ticket/11756 can somebody comment and/or apply it please? I'm not trying to be pushy, just writing here since it seems that it can happen that people see traffic on a bug, but don't realise that a patch was attached. Thanks! Andre'

2 2

Boost-1.62: How to get list of all dirs under 'run-tests libs:' target from status/Jamfile?
by Sergey Sprogis 04 Sep '16

04 Sep '16

I use latest Boost versions to test new C++ compiler in development stage. It's important for me to know what would be "pass rate" for every library which Boost.org reports on its Regression Testing website. To calculate all those pass rates I created script which goes inside every library's 'test', 'example' or whatever subdirectory and launches bjam from there. It creates a separate logfile(s) for every library which I then analyze to calculate "pass rate". But before launching my script I need to know the whole list of dirs which Boost.org uses for its Regression testing. In the previous Boost-1.61.0 version I was able to easily produce such list by extracting it from 'status/Jamfile.v2'. It looked like this: run-tests libs : accumulators/test # test-suite accumulators algorithm/test # test-suite algorithm algorithm/minmax/test # test-suite algorith/minmax ... concept_check # test-suite concept_check config/test # test-suite config container/bench # test-suite container benchmarks container/example # test-suite container_example ..... As you may see this list contains not only 'test' subdirs, but also some others: 'example', 'bench', etc. But now the problem is that in Boost-1.62.0 'status/Jamfile.v2' does not have such full list anymore. Could anyone suggest me some hack how to produce the full list of tested libraries for Boost-1.62.0, similar to one which Boost-1.61.0 has? It would be nice if bjam will eventually have a special option which will allow to produce such list, but for now I'd appreciate just a hack which will help me to solve this issue. Thanks, Sergey

2 1

[test] Unrecognized option -u
by Andrey Semashev 03 Sep '16

03 Sep '16

Hi, I'm seeing test errors about unrecognized option -u presumably from Boost.Test, see here for example: http://www.boost.org/development/tests/develop/developer/output/teeks99-09b… The test in question is not mine, and I don't know what the -u option is supposed to be for, but I assume it was supported by Boost.Test at some point and now it isn't. Is this an intended change in Boost.Test, an oversight or just a mistake in the Jamfile? If it was supported by Boost.Test, what did the option do and is it ok to just remove it?

3 4

[release] Can I push a bug fix?
by Andrzej Krzemienski 01 Sep '16

01 Sep '16

Hi all, Do I need permission now to push a bug fix to master? I intend to put this fix: https://github.com/boostorg/optional/commit/5d5d1f46baac851c8ec0ca15059d3e7… Regards, &rzej;

2 1

Please add component "dll" to track
by Antony Polukhin 31 Aug '16

31 Aug '16

Subj. Thanks! -- Best regards, Antony Polukhin

1 0

compiling boost using C++11 atomics
by André Draszik 30 Aug '16

30 Aug '16

Hi, Is there any particular reason that boost isn't being compiled with BOOST_AC_USE_STD_ATOMIC and BOOST_SP_USE_STD_ATOMIC (by default) when C++11 support in g++ is available (g++ >= 4.7)? Thanks, Andre'

3 5

[PropertyTree] Pull request removing usage of typeid()
by Chris Glover 29 Aug '16

29 Aug '16

Hi, In February, I submitted a pull request that removes the usage of typeid from property_tree and replaces it with boost.type_index. This allows me to use property_tree with rtti disabled, which I need sometimes. https://github.com/boostorg/property_tree/pull/20 I've had no feedback on the change. Can it be merged? Thanks, -- chris

2 2

[graph] Dinic's algorithm and BGL
by Зайцев Александр 29 Aug '16

29 Aug '16

Hello. In the Boost Graph Library i can't find Dinic's algorithm (https://en.wikipedia.org/wiki/Dinic%27s_algorithm) I think there isn't implementation of this algo in the library. Why? Best regards, Alexander Zaitsev.

2 2

[algorithm] Adding suffix automata, suffix array
by Зайцев Александр 29 Aug '16

29 Aug '16

Hello. I implemented Aho-Corasick to Boost.Algorithm. It's very useful algorithm, but i think that there are more useful algorithms, like suffix automata and suffix array. They can solve a lot of specific task on sequences of values: searching subsequences, count number of different subsequence, etc. Can i start work on it? ----- Best regards, Alexander Zaitsev.

2 3

[Boost.Book] How to go full-bleed on documentation image headers?
by Vinnie Falco 29 Aug '16

29 Aug '16

On the Boost website, the image in documentation headers is full bleed (no white border). For example: http://www.boost.org/doc/libs/1_61_0/doc/html/boost_asio.html How do I achieve this in my own documentation? I have set the image in the Jamfile, but I have no idea how to adjust the border: http://vinniefalco.github.io/beast/index.html The Jamfile and supporting source files are here: https://github.com/vinniefalco/Beast/tree/master/doc Thanks

2 1

[predef] macro to detect OS version on Solaris
by Aparna Kumta 28 Aug '16

28 Aug '16

I looked at the predef documentation and see BOOST_OS_SOLARIS macro to detect the Solaris OS. Is there a way I can detect the Solaris version? Thanks, Aparna | | <http://www.boost.org/doc/libs/1_61_0/libs/predef/doc/html/predef/reference/…>

3 2

[algorithm] Discuss about Aho-Corasick implementation
by Зайцев Александр 28 Aug '16

28 Aug '16

Hello. I implemented Aho-Corasick for Boost.Algorithm. I think that a lot of developers are interested in this and can look through my code and guess some suggestions. You are welcome: https://github.com/ZaMaZaN4iK/algorithm/blob/feature_branch/aho_corasik/inc… -- Best regards, Alexander Zaitsev

1 0

[Root.Ptr] Review Schedule Listing Fix
by Phil Bouchard 27 Aug '16

27 Aug '16

Greetings, In the formal review schedule page: http://www.boost.org/community/review_schedule.html Is it possible for somebody to: - Change the name of the submission "Block Pointer" to "Root Pointer" - Point the source code to: https://github.com/philippeb8/root_ptr - Point the documentation to: http://philippeb8.github.io/root_ptr This way people will at least be able to read something about Root.Ptr! ;) Regards, -Phil

2 2

[test] request to integrate a bugfix to master
by Raffi Enficiaud 26 Aug '16

26 Aug '16

Dear all, Please move boost.test to rev f68df446a4a5a3873e262364b56c5c2446216ae6 as it contains an important bug fix in case header only version of boost.test is used. Thanks and sorry for the noise, Raffi

2 1

[test] All geometry regression tests failing in develop and master
by Rene Rivera 25 Aug '16

25 Aug '16

Tagging subject for visibility. But this obviously needs to get resolved ASAP.. On Wed, Aug 24, 2016 at 3:53 AM, Barend Gehrels <barend(a)xs4all.nl> wrote: > Hi, > > It seems that nearly all regression tests are failing for us in both > develop and master: > > http://www.boost.org/development/tests/master/developer/geometry.html > > With the messages like: > > disjoint.obj : error LNK2001: unresolved external symbol > "public: virtual void __cdecl boost::unit_test::output::juni > t_log_formatter::log_start( > class std::basic_ostream<char,struct std::char_traits<char> > &,unsigned > long)" > (?log_start@junit_log_formatter@output@unit_test@boost@@ > UEAAXAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@K@Z) > > > We use Boost.Test (header-only), is there something changed there? Do we > need to change our Jam file? (of course we want to keep it header-only). > > The failures are new, before my one-week holiday it was still all OK. > > Regards, Barend -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

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]dynamic_bitset] develop change never merged to master
by Edward Diener 25 Aug '16

25 Aug '16

In going through the CMT libraries for the upcoming release I noticed a longstanding change to dynamic_bitset on the 'develop' branch that added capacity, reserve, and shrink_to_fit functionality which had never been merged to the 'master' branch. The change is purely to add functionality rather than a bug fix, but it has been tested successfully on the 'develop' branch for a long while now. Do we want this functionality in the upcoming release ? If not, this change can be merged to 'master' after the release is out for the next release.

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[release] Boost 1.62 now closed.
by Rene Rivera 25 Aug '16

25 Aug '16

Reminder.. The Boost 1.62 release, i.e. master branches, are now closed. Any change requires approval from a release manager. The release will reopen for bug fixes a week from now after the beta is posted. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

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All geometry regression tests failing in develop and master
by Barend Gehrels 24 Aug '16

24 Aug '16

Hi, It seems that nearly all regression tests are failing for us in both develop and master: http://www.boost.org/development/tests/master/developer/geometry.html With the messages like: disjoint.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl boost::unit_test::output::junit_log_formatter::log_start( class std::basic_ostream<char,struct std::char_traits<char> > &,unsigned long)" (?log_start@junit_log_formatter@output@unit_test@boost@@UEAAXAEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@K@Z) We use Boost.Test (header-only), is there something changed there? Do we need to change our Jam file? (of course we want to keep it header-only). The failures are new, before my one-week holiday it was still all OK. Regards, Barend

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[Quickbook] Quickbook, SVG, graphviz dot
by Matt Calabrese 23 Aug '16

23 Aug '16

This is something of a stretch, but I'm hoping someone has a simple solution to my problem. I'm using Quickbook and in my docs I'm including an SVG that I generated from a graphviz dot file, which was also automatically generated from code that I'm documenting. Inside each of the nodes in the graph contained in the SVG, I would like to have source code snippets that are formatted in a way that is consistent with code snippets that are embedded in Quickbook files. Ideally, I'd like to even include Quickbook links in that source code, though I think that's likely a bit harder (my Quickbook code snippet files are usually written in a way that compiles in C++ but on the Quickbook end also replaces known functions with links to their corresponding docs -- I'd like to have that even in the nodes of the generated graph). I'm not certain where precisely to start as I'm rather far outside of my usual domain here. I pretty sure that it must be feasible in some way, as I know that SVG can embed links and use css, etc. but I'm not sure precisely how I should try to tackle this. Perhaps I can create some kind of post-process to run on the SVG that was generated from the dot file? Is there something simpler than this? Any ideas are appreciated. -- -Matt Calabrese

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Re: [boost] double_ended - request formal review
by Mathias Gaunard 23 Aug '16

23 Aug '16

On 15 July 2016 at 16:51, Benedek Thaler <thalerbenedek(a)gmail.com> wrote: > Dear Boost, > > I'd like to request the review of the double_ended library. > > Code: https://github.com/erenon/double_ended > Documentation: http://erenon.hu/double_ended > > The library contains two classes. Excerpt from the documentation: > > * `devector` is a hybrid of the standard vector and deque containers, as > well as the small_vector of Boost.Container. It offers cheap (amortized > constant time) insertion at both the front and back ends, while also > providing the regular features of std::vector, in particular the contiguous > underlying memory. In contrast to the standard vector, however, devector > offers greater control over its internals. Like small_vector, it can store > elements internally without dynamically allocating memory. Not related to your request per-se, but I think this occasion is as good as any to discuss the library. devector is an interesting variant of vector, but it gives the illusion that is could be used as a queue. However given the implementation, it seems elements removed from either end will never be reclaimed. I suggest documenting that limitation or having a threshold above which memory is actually freed.

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[CallableTraits] Seeking Review Manager
by Barrett Adair 23 Aug '16

23 Aug '16

Boost Developers, CallableTraits is a C++11/14/17 library for the inspection, synthesis, and decomposition of callable types. CallableTraits aims to be the "complete type manipulation facility for function types" mentioned in the final paragraph of C++17 proposal p0172. Library: https://github.com/badair/callable_traits Docs: http://badair.github.io/callable_traits/doc/html/index.html Boost Library Incubator: http://blincubator.com/bi_library/callabletraits-2/?gform_post_id=1574 Current Version: 1.0.1 I've received some great feedback on the mailing list. I consider the current version to be production-ready, which includes excellent cross-platform test coverage and thorough documentation filled with examples. Does anyone wish to be a review manager for this library? It is not a very large codebase, although the implementation is config-heavy and relatively noisy. The Library Submissions page on the Boost website indicates that a library manager should be found before requesting a formal review, but I noticed that there are many "scheduled reviews" that do not have a library manager. May I request a review as well? Thank you, Barrett

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[release] Boost 1.62 closed for major changes.
by Rene Rivera 19 Aug '16

19 Aug '16

Reminder Boost 1.62, i.e. the master branches, are now closed for major changes. The only changes that should be going in at this time should be bug fixes for serious problems. Any documentation changes are fine to go in. And remember... Boost 1.62 will close for all changes a week from today. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

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[odeint ] Can fix for ticket #12034 be merged into master branch?
by Aparna Kumta 19 Aug '16

19 Aug '16

The fix for Boost ticket #12034 has been in the develop branch for about 6 months now. Could this please be merged into the master branch so it makes it in for Boost 1.62 release? Thanks, Aparna

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[circular_buffer] Synchronize master with develop
by Andrey Semashev 18 Aug '16

18 Aug '16

Hi, I've created this PR to synchronize master with develop for Boost.CircularBuffer: https://github.com/boostorg/circular_buffer/pull/10 Rene has given the permission to merge in the "[boost] [release] Boost 1.62 closed for major changes." thread. I would appreciate if someone with permissions could merge the PR. Thanks.

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Status on Travis
by Raffi Enficiaud 18 Aug '16

18 Aug '16

Hi dear list, Hi Rene, I would like to know more about Travis and its status. From what I understand, a lot of efforts have been made recently for making things running per commit on Travis and have a quick feedback. * Naturally the first question is: is the status given by Travis the "official" one? so we consider the status given by Travis an official source of information, especially wrt. to its competing regression dashboard. * What are the development plans for Travis? Right now I see 3 types of builds, and I do not fully understand what they cover (platform, compiler) nor their differences. * For boost.test, I am testing each feature branch before merging to develop, by 1. cloning boost superproject on develop 2. switching only boost.test to the feature branch This is for preventing the breakages on develop that we observed in the past since several libraries are depending on boost.test. Would it be possible to have that as well on Travis or any continuous CI? That would be per library then. Would it also be possible to have like a template .travis.yml coming from the boost.superproject which can partly be overiden by a library? (if we want to build things slightly differently) * The CI I am using is able to parse the junit files generated by the test framework, and summarizes the information of each build nicely (also tracks the tests history). Is there anything similar in Travis? Right now, apart from looking at the full logs (which is hard), is there any intermediate information than red/green overall status? * I can see many project under the boostorg of Travis https://travis-ci.org/boostorg/ . How do we do that? Thanks, Raffi

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[Beast] Status: HTTP+WebSocket for Boost
by Vinnie Falco 17 Aug '16

17 Aug '16

I’m reporting on the status of Beast, a C++11 header-only library implementing HTTP and WebSocket which is submitted to the boost incubator. The official repository for Beast is at: https://github.com/vinniefalco/Beast It has been a few months since the last update and the number of users measured on GitHub has grown steadily. There is robust, active development with bug fixes and improvements. Unfortunately there hasn’t been much of in terms of attention from the Boost community, no feedback from the incubator was provided. If anyone would like to help out by checking out Beast in the incubator and leaving some comments that would be a tremendous help. Incubator link: http://blincubator.com/bi_library/beast-2/?gform_post_id=1579 The most exciting news is that Beast HTTP and WebSockets have been deployed in the production server environment for the company I work for, Ripple (http://ripple.com) On a side note, my co-worker David Schwartz is giving a CppCon 2016 Keynote speech on the relationship of C++ to public blockchain systems and cryptocurrencies: http://cppcon.org/schwartz-keynote-turner-plenary/ You can see the Beast integration in “rippled”, an open source server application that implements Ripple’s decentralized ledger: https://github.com/ripple/rippled/tree/develop/src/ripple/server/impl I will be doing a 15 minute lightning talk introducing CppCon 2016 conference attendees to Beast. The talk will have 8 minutes of presentation with the remainder of the time allocated for questions (if there are no questions I have additional materials which can be presented). At the conference I would love to meet anyone who is interested in the library or wants to have their questions answered - feel free to reach out to me through my email address vinnie.falco(a)gmail.com (also listed on my GitHub profile) if you’d like to get in contact. Thanks! -- Follow me on Github: https://github.com/vinniefalco/Beast

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[contract] Contracts for constexpr functions
by Lorenzo Caminiti 16 Aug '16

16 Aug '16

Hello all, A couple of the proposals I read on adding Contract Programming to the C++ standard raise the question if contracts should be supported for constexpr functions or not. I tough about this question a bit... but I am still not sure of the answer. I wanted to discuss this topic with this mailing list, especially with respect to what Boost.Contract can currently do. My general impression is that preconditions, postconditions, and class invariants should useful for constexpr functions but noting that: * Probably old values will not be useful in constexpr functions because constexpr prevents its functions from having side-effects (so it seems there will no variable visible outside of the function that the function body can change, and those variables are usually the candidates for making old copies). * Subcontracting will never apply to constexpr functions because they cannot be virtual. For example: struct conststr { // No virtual function so no subcontracting. [[invariant: empty() == (size() == 0)]] // Useful class invariants. [[invariant: data() != nullptr]] template<unsigned N> constexpr conststr(char const (&s)[N]) [[requires: s != nullptr]] // Useful preconditions. : data_(s), size_(N - 1) {} constexpr char back() const [[ensures(result): result == data()[size() - 1]]] // Useful postconditions. // Old values never useful because constexpr has no side-effects? { return data_[size_ - 1]; } constexpr unsigned size() const { return size_; } constexpr bool empty() const { return size_ == 0; } constexpr char const* data() const { return data_; } private: char const* data_; unsigned size_; }; That said, if I understand it correctly, the following are not allowed from within constexpr functions: 1. (Literal) type local variables with non-trivial constexpr destructors (see N3597 and subsequent proposals). 2. Try-catch statements (see N3597 and subsequent proposals). 3. Lambda functions (see N4487). Reading a few proposals, it seems that supporting the above from constexpr functions would be technically possible, but difficult to implement (see N3597 and its subsequent proposals, N4487, etc.). I'm not really familiar with these constexpr restrictions and plans/discussions to relax them in future revisions of the standard... Boost.Contract implementation uses all the above 1-2-3 respectively to: a. Check class invariants and postconditions at function exit (using RAII). b. Catch assertion failures as well as any other exception that might occur while evaluating an asserted conditions and then call the appropriate contract failure handler. c. Conveniently program functors that check pre- and postconditions within the contracted function. Therefore Boost.Contract implementation does not currently support contracts for constexpr functions. --Lorenzo

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