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[release] Is everyone ready for the 1.72.0 release (cycle)?
by Marshall Clow 21 Oct '19

21 Oct '19

We're getting ready to start the release cycle. People should be familiar with the milestones. They're on the calendar at https://www.boost.org/development/ The first two milestones are: 23-Oct: Boost 1.72.0 closed for new libraries and breaking changes 30-Oct: Boost 1.72.0 closed for major changes -- Marshall

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[Exception] PR #24 passes CI tests
by dariomt＠gmail.com 21 Oct '19

21 Oct '19

Hi, PR #24 [1] at last passes all CI tests. It should solve Issue #10 [2]. I'd like to ask for it to be reviewed and merged. I'm hopeful we can get it into the 1.72 release. Regards, Dario PS: thanks to pdimov for suggesting how to fix the Travis configuration [1] https://github.com/boostorg/exception/pull/24 [2] https://github.com/boostorg/exception/issues/10

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Re: [boost] Adding my sorting algorithm, ska_sort to boost
by Malte Skarupke 20 Oct '19

20 Oct '19

Thanks for the replies. I finished a first pass of the documentation, tests, and other work of including my algorithm in boost and uploaded it here: https://github.com/skarupke/sort/tree/master I also re-ran all the single threaded benchmarks and updated the documentation. For the big O complexity: I am actually still not quite sure what it is. I used similar notation to what spreadsort uses. I think O(n*key_length) is correct for the worst case, but for long keys (like when sorting long strings) the algorithm may fall back to comparison based sorting, so I used the same thing as spreadsort: min(O(n log n), O(n key_length)). For speed: ska_sort should be the fastest sorting algorithm even for small numbers of items. I included three graphs of benchmarks, for sorting ints, floats and strings: https://github.com/skarupke/sort/blob/master/doc/images/sorting_ints.png https://github.com/skarupke/sort/blob/master/doc/images/sorting_strings.png https://github.com/skarupke/sort/blob/master/doc/images/sorting_floats.png For ints and strings ska_sort is always fastest, for floats pdqsort is briefly faster, but starting at N >= 128 ska_sort is faster. Part of the work of this new version of ska_sort was to make radix sort really fast even for small N. Before I would use std::sort for any small array of less than 128 items. Now that cutoff is at 32 items, so I skip straight to insertion sort and never do std::sort. The biggest effect of this change is that it removes the "waves" from the benchmark graph, like we still see for spreadsort in the above picture. I used to also have those when I gave a talk about this algorithm. Now the graph is much more smooth. (this also confuses my answer to the question "what is the big O complexity of this algorithm?" Because the O(n*b) answer that I gave in my talk was justified by the presence of the waves) The biggest questions I have at this point are around the interface. I reworked that completely so that even relatively advanced use cases are now pretty straightforward. I don't think that anyone else will ever need to use those advanced features, so I kept the documentation of them small, choosing instead to focus on the common use cases. And I made sure to give lots of examples of converting existing comparison-based sorting examples to my interface. Oh and for the big point of a parallel version of this algorithm: At this point I have no idea how to do that. I haven't even begun to look into parallel algorithms. The current version was a lot of work already. I think that'll have to be a project for another time. (it's definitely appealing though since currently the sorted algorithms are only 2.4 times as fast as ska_sort on a machine with 8 cores/16 hyper threads in benchmark_numbers.cpp, so even a little bit of parallelism would beat the existing algorithms...) Francisco, since you'll be busy in the near term it sounds like I can't expect too much response for another month, but I would really appreciate it if you could look at it a little just to see if anything obvious stands out to you that I can work on while I wait. (otherwise no biggie, I understand how hard it can be to find time for maintaining projects, since that is exactly one of the reasons why I want to get this into boost...) Thanks, Malte -- Malte Skarupke malteskarupke(a)fastmail.fm > Date: Sun, 20 Oct 2019 13:24:06 +0200 > From: Francisco Jos? Tapia <fjtapia(a)gmail.com> > To: boost(a)lists.boost.org > Subject: Re: [boost] Adding my sorting algorithm, ska_sort to boost > Message-ID: > <CADBNGqQJpHux3AdRJON-nh76BaouRn1FRO4_LrMR76TywmCH+g(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hi Malte, > I am Francisco Tapia, one of the co-authors of the Sort library. > We will examine your algorithm. But we must examine the internal parts of > the algorithm, and evaluate the correctness of the algorithm, how is > implemented the worst case and a couple of details. After, we check the > speed with the benchmarks used in the library, with several sets of data. > Since the near sorted to the fully unsorted, and from the single numbers to > structs with heavy comparison functions. > > Now, I am overburdened by work, and I can't revise until December. But we > will do and provide to you a reasoned response, and according to it, decide > the inclusion or not in the library. > As commented by Phil Endecott, the most interesting now is the parallel > algorithms. Today, we don't have any parallel algorithm based on radix sort > or any other hybrid algorithm. > Because with small sets of data the differences are insignificant. But when > you have big sets of data, use parallel algorithms, and then, the new > single thread algorithms are in the middle, in the no man's land. > > If you have any doubt or question, contact me, and I will try to answer you. > > El mar., 15 oct. 2019 a las 23:06, Kostas Savvidis via Boost (< > boost(a)lists.boost.org>) escribi?: > > > > > > On Oct 13, 2019, at 03:06, Malte Skarupke via Boost < > > boost(a)lists.boost.org> wrote: > > > > > > Hi, > > > a couple of years ago I wrote a generalized version of radix sort, > > called ska_sort. I gave a talk about it at CppNow, available here: > > > https://www.youtube.com/watch?v=zqs87a_7zxw > > > > > > I have a new version of that algorithm that is both faster and more > > general. I can now sort almost anything. For example when I gave the talk I > > couldn't sort a std::vector<std::list<int>> because std::list doesn't have > > a random access interface, but now that works. (and it's faster than > > sorting the same thing with std::sort) > > > > > > > This seems like a product of a large investment of effort. > > The big advantage over any previously available radix_sort > > is the ability to sort almost any datatype if a key maps to an integer > > somehow. > > Plus, an advantage in measured practical speed, and apparently no claims > > about Big O improvement. > > > > The average performance is O(n*b) where b is unknown and/or dependent on n > > ? > > > > Is the theoretical worst-case O(n^2) ? Why? Is it because of working > > in-place? > > (yes, I understand you fall back to std::sort if you hit this case) > > > > Is this software/algorithm fully documented? - I mean by another way than > > reading the source code. > > > > Maybe too many questions at once, but it was not clear after watching your > > talk at cppcon and the blog posts. > > > > Cheers, > > Kostas > > > > <https://www.youtube.com/watch?v=Nz1KZXbghj8> > > > > _______________________________________________ > > Unsubscribe & other changes: > > http://lists.boost.org/mailman/listinfo.cgi/boost > > > > > ------------------------------ > > Subject: Digest Footer >

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constexpr for boost::endian
by Gero Peterhoff 20 Oct '19

20 Oct '19

Hello developer, can you implement constexpr support for boost::endian? And i'm missing support for (compiler-dependent) int128 (boost::u/int128_type). thx Gero

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Adding my sorting algorithm, ska_sort to boost
by Malte Skarupke 20 Oct '19

20 Oct '19

Hi, a couple of years ago I wrote a generalized version of radix sort, called ska_sort. I gave a talk about it at CppNow, available here: https://www.youtube.com/watch?v=zqs87a_7zxw I have a new version of that algorithm that is both faster and more general. I can now sort almost anything. For example when I gave the talk I couldn't sort a std::vector<std::list<int>> because std::list doesn't have a random access interface, but now that works. (and it's faster than sorting the same thing with std::sort) I've also made it much easier to extend the algorithm with your own types. It was always easy if your type isn't too complicated, but now even weird types like std::variant are pretty easy to add. In my old version I had to go deep into the guts to add support for std::variant, now it's easy enough to do that that I'll add it to the documentation. I'm thinking of releasing the new version in boost, mainly so that it will be used more widely and so that it can be kept working in the long term. Since this is a long weekend in the US, I will try to as much of the work as possible this weekend. I'm currently trying to figure out how the boost documentation works (I saw that there are quickbook files in Boost.Sort, but how do I run the build for it?) and I've already made good progress on cleaning up my code and making it use the boost::sort namespace. Before I go any further I wanted to ask though: Does boost want my sorting algorithm? This would essentially deprecate spreadsort since this one is faster and more general and easier to use. To convince you that this is worth adding, I ran the benchmark that is included in the Boost.Sort source code. On random numbers here is how long all the algorithms took: std::sort: 9.04 pdqsort: 4.65 std::stable_sort: 11.57 spinsort: 5.42 flat_stable_sort: 7.26 spreadsort: 4.41 ska_sort: 2.00 There are a lot more bencmarks in the Boost.Sort code, and in general the results are this: If the data is already sorted or mostly sorted, other algorithms are faster, but if there are no easy patterns, ska_sort is always fastest. (I was going to include the entire table in this email, but the formatting breaks. I can attach all the results separately if anyone is interested) The Boost.Sort code also has benchmarks for sorting "objects" and "strings" and the results are similar there: On random data ska_sort is always fastest. I think this new version would be great in boost. It's not every day that a new sorting algorithm comes along that's literally twice as fast as what we had before. If we want this in boost, what would the next steps be? From the "submission process" document it sounds like there will be several stages of "Refinement" for the code. (or should this go through the Boost Library Incubator?) After I figure out how the documentation works I can upload a first version of this to github. (I want to get the documentation working so that we can talk about the interface) Let me know what you think, Malte -- Malte Skarupke malteskarupke(a)fastmail.fm

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[SPAM] [preprocessor][vmd] Updates to the preprocessor and vmd libraries
by Edward Diener 19 Oct '19

19 Oct '19

The C++20 preprocessor construct __VA_OPT__ has the additional affect of providing the ability to write a general purpose macro for testing emptiness, ie. no preprocessor tokens, in C++ macro programming that is 100% reliable for any preprocessor data passed to it. Previously such a macro testing for emptiness always had some corner cases where the test might fail with a preprocessor error, but in C++20 mode at least the test can now be completely reliable in all cases. So I have added two macros along with documentation, as well as a topic discussing emptiness, to the Boost PP library. The first macro is called BOOST_PP_VARIADIC_OPT, invoked with no parameters as BOOST_PP_VARIADIC_OPT(), which expands to 1 if the compiler is in C++20 mode, supports variadic macros, and supports the C++ 20 __VA_OPT__ construct, and otherwise expands to 0. The second macro, which only exists if BOOST_PP_VARIADIC_OPT() expands to 1, is called BOOST_PP_CHECK_EMPTY. This second macro is a variadic macro which takes a single parameter of variadic data, and expands to 1 if the data is empty or expands to being empty, while otherwise expanding to 0 if the data is not empty. Furthermore in the Boost VMD library I have updated the BOOST_VMD_IS_EMPTY macro to essentially invoke the BOOST_PP_CHECK_EMPTY macro when BOOST_PP_VARIADIC_OPT() expands to 1, while retaining the current processing when that is not the case. As well I have updated the VMD discussion of emptiness in the documentation of Boost VMD to include information about the ability to provide a 100% reliable test for emptiness in C++20. Neither change in Boost PP or Boost VMD should affect any end-user or Boost library in any way. There are tests for all these changes and all tests have passed. I will update the release notes for Boost PP and Boost VMD for the next release of Boost with this information. As always any comments, questions, or criticism of these changes are always welcome.

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Warning from Boost.Exception
by pbristow＠hetp.u-net.com 17 Oct '19

17 Oct '19

Using Clang 9 on Windows b2 toolset-clang-linux cxxstd=2a . I am seeing lots of these warnings In file included from ..\..\..\boost/test/included/unit_test.hpp:23: In file included from ..\..\..\boost/test/impl/execution_monitor.ipp:37: In file included from ..\..\..\boost/exception/diagnostic_information.hpp:11: ..\..\..\boost/exception/info.hpp:134:21: warning: delete called on non-final 'boost::exception_detail::error_info_container_impl' that has virtual functions but non-virtual destructor [-Wdelete-non-abstract-non-virtual-dtor] delete this; ^ It seems that trying to supress is ineffective with -Wno-delete-non-abstract-non-virtual-dtor Perhaps by design? https://releases.llvm.org/9.0.0/tools/clang/docs/DiagnosticsReference.html#… te-non-abstract-non-virtual-dtor -Wdelete-non-abstract-non-virtual-dtor <https://releases.llvm.org/9.0.0/tools/clang/docs/DiagnosticsReference.html> Diagnostic text: warning: delete destructor called on non-final B that has virtual functions but non-virtual destructor -Wdelete-non-virtual-dtor <https://releases.llvm.org/9.0.0/tools/clang/docs/DiagnosticsReference.html> Some of the diagnostics controlled by this flag are enabled by default. Controls -Wdelete-abstract-non-virtual-dtor <https://releases.llvm.org/9.0.0/tools/clang/docs/DiagnosticsReference.html> , -Wdelete-non-abstract-non-virtual-dtor <https://releases.llvm.org/9.0.0/tools/clang/docs/DiagnosticsReference.html> . Should I be concerned about this? Paul Paul A. Bristow Prizet Farmhouse Kendal, Cumbria LA8 8AB UK

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[Math] float16 on ARM
by Phil Endecott 16 Oct '19

16 Oct '19

Hi, There seems to be support for 16-bit floats on iOS, when using Apple's XCode clang. This seems to be a storage-only format with the only instruction set support being conversions to and from 32- and 64-bit floats. Quick test: #if __ARM_FP & 2 #warning "Have 16-bit FP" #endif void test() { __fp16 a = 1.234; static_assert(sizeof(a)==2); __fp16 b = 2.345; auto sum = a+b; static_assert(sizeof(sum)==4); } There doesn't seem to be a std::numeric_limits specialisation. I suspect that other platforms have something similar. It would be good to have a boost::float16_t typedef and a portable feature-test macro (and maybe a software fallback). As far as I can see, boost/math/cstdfloat/cstdfloat_types.hpp checks the sizes of float, double and long double, and checks for 128-bit floats provided by the compiler. Can this be extended to check for __fp16 ? (P.S. it seems that gcc also has support, see https://gcc.gnu.org/onlinedocs/gcc/Half-Precision.html ) Cheers, Phil.

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Does boost asio ssl support sslv3?
by JH 15 Oct '19

15 Oct '19

Hi, I've been running boost asio socket and sslv2 for many months, it works very well: server.cpp ontext_(boost::asio::ssl::context::sslv23) context_.set_options(boost::asio::ssl::context::default_workarounds | boost::asio::ssl::context::no_sslv2 | boost::asio::ssl::context::single_dh_use); context_.set_password_callback(boost::bind(&Server::get_password, this)); context_.use_certificate_chain_file("ssl/server.pem"); context_.use_private_key_file("ssl/server.pem", boost::asio::ssl::context::pem); context_.use_tmp_dh_file("ssl/dh2048.pem"); on client.cpp boost::asio::ssl::context context(boost::asio::ssl::context::sslv23); Recently we changed a nodejs server nodejs which using sslv3, the client failed to connect to server sslv3: Failed handshake: sslv3 alert handshake failure Any tips how to fix sslv3 handshake failure? Thank you. Kind regards, - jh

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Cryptic Boost.Build error (help required!)
by John Maddock 14 Oct '19

14 Oct '19

Can anyone see what's wrong here: https://github.com/boostorg/regex/issues/89 ? The reduced test case is: |./b2 -sICU_PATH="/opt/some/path" -sICU_LINK="-L/opt/some/path/lib/x86_64-linux-gnu -licuuc -licudata -licui18n" toolset=gcc-8 -n --with-filesystem --with-log Many thanks, John. | -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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[gil][docs] Image Processing docs structure based on "Principles of Digital Image Processing" book
by Mateusz Loskot 13 Oct '19

13 Oct '19

Hi, (Copying to boost and boost-users lists) If you are passionate about C++ and image processing and interested in writing documentation about it, here is a good first issue for you if you'd like to start contributing to Boost.GIL. During the course of GSoC 2019 we have received first batch of IP features, there is not great deal of content yet, so shouldn't be overwhelming to get started. It's rather a clean slate under your control. Don't be shy! :-) Regards, Mateusz Loskot ---------- Forwarded message --------- From: Mateusz Loskot <mateusz(a)loskot.net> Date: Sun, 13 Oct 2019 at 20:08 Subject: [GH #396] Image Processing docs structure based on "Principles of Digital Image Processing" book To: <boost-gil(a)lists.boost.org> Hi, Following our successful GSoC 2019, I have started discussion on proposal of improved and future-proof structure of the "Image Processing" chapters of GIL documentation. Here are details: https://github.com/boostorg/gil/issues/396 Please, have a look and share your feedback. If there is anyone experienced in writing docs, a technical write, who is looking for ways to contribute to Boost and Boost.GIL, this is a very good first issue to pick :-) Best regards, -- Mateusz Loskot, http://mateusz.loskot.net -- Mateusz Loskot, http://mateusz.loskot.net

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[outcome] Major changes for Boost 1.72 release
by Niall Douglas 11 Oct '19

11 Oct '19

Just as a heads up to those who care, and any pretesting of these changes in advance of the Boost release is welcome. There are two breaking changes: 1. The git submodule mechanism used by standalone Outcome of specifying dependent libraries has been replaced with a cmake superbuild of dependencies mechanism instead. Upon cmake configure, an internal copy of quickcpplib will be git cloned, built and installed into the build directory from where an internal `find_package()` uses it. This breaks the use of the unconfigured Outcome repo as an implementation of Outcome, one must now do one of: 1. Add Outcome as subdirectory to cmake build 2. Use cmake superbuild (i.e. `ExternalProject_Add()`) to build and install Outcome into a local installation. 3. Use one of the single header editions. 2. For standalone Outcome, the current compiler is now checked for whether it will compile code containing C++ Concepts, and if it does, all cmake consumers of Outcome will enable C++ Concepts. Set the cmake variable `CXX_CONCEPTS_FLAGS` to an empty string to prevent auto detection and enabling of C++ Concepts support occurring. There are two new features: - Standalone outcome is now `make install`-able, and cmake `find_package()` can find it. Note that you must separately install and `find_package()` Outcome's dependency, quickcpplib, else `find_package()` of Outcome will fail. - Support for C++ Coroutines has been added. This comes in two parts, firstly there is now an `OUTCOME_CO_TRY()` operation suitable for performing the `TRY` operation from within a C++ Coroutine. Secondly, in the header `outcome/coroutine_support.hpp` there are implementations of `eager<OutcomeType>` and `lazy<OutcomeType>` which let you more naturally and efficiently use `basic_result` or `basic_outcome` from within C++ Coroutines -- specifically, if the result or outcome will construct from an exception pointer, exceptions thrown in the coroutine return an errored or excepted result with the thrown exception instead of throwing the exception through the coroutine machinery (which in current compilers, has a high likelihood of blowing up the program). Both `eager<T>` and `lazy<T>` can accept any `T` as well. Both have been tested and found working on VS2019 and clang 9. More detail can be found at: https://boostorg.github.io/outcome/changelog.html Niall

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Seeing spam designation in message title
by Edward Diener 10 Oct '19

10 Oct '19

The previous message I sent to this mailing list shows the word [SPAM] in the title to the message. Does anybody know why this happened ? I am obviously not a spammer being the author of two libraries and maintainer of another.

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Regression tests on 'develop'
by Edward Diener 10 Oct '19

10 Oct '19

It looks like on the 'develop' side most regression tests are either not being run very often or there is some problem in the posting of the latest results. I suspect the former but I thought it should at least be brought up. On the 'master' side many more recent recent regression tests are showing.

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A solution to return dynamic strings without heap allocation. Any interest?
by Roberto Hinz 09 Oct '19

09 Oct '19

Hi all, I haven't been succesful at attracting interest in a formatting library [1] I've been working lately. But recently I realized that part of it could be isolated as a small standalone library that could solve an old common troublesome situation in C++: Suppose you need to create a function that returns/provides a string whose content and size is unknown at compilation time. The first approach is to make it return a `std::string`. But if it need to be usable in environments like bare-metal real-time system, then one usually makes it take a raw string as an output argument, more or less like this: struct result{ char* it; bool truncated; }; result get_message(char* dest, std::size_t dest_len); But this is clearly not a perfect solution since there's nothing really effective the caller can do when get_mesage fails because of the destination string being is too small. So I present the `outbut` abstract class. It somehow resembles `std::streambuf`, but with a simpler and lower level design, which is the result of many attempts looking for the best performance [2] and usability in my formatting library. Afaics, it does not require a hosted C++ implementation, though I would like someone else to confirm that. Now the caller of `get_message` has to choose or create a suitable class type deriving from outbuf, that dictates where the message is written to. For example, if the user wants to get a `std::string`, then `string_maker` will do the job: #include <boost/outbuf/string.hpp> // ... boost::outbuf::string_maker<false> msg; get_message(msg) std::string str = msg.finish(); Or, if one wants it to write into a raw string, then use `cstr_writer` char buff[buff_size]; boost::outbuf::cstr_writer csw(buff, buff_size); get_message(csw); auto result = csw.finish(); if (result.truncated) { // ... Those `finish` functions above do not belong to `outbuf`. They are defined in the concrete derived types only. It's solely by convention that they share the same name. Yes, using `string_maker` still leads to heap allocation and `cstr_writer` to string truncation. The problem isn't solved by these. However, a string object is never the final destination. So the user could rather use another class that writes the message directly into the final destination ( output console, a log file, an LCD display or whatever ). It is not difficult to implement concrete subtypes of `outbuf`. `outbuf` is actually a type alias: template <bool NoExcept, typename CharT> class basic_outbuf; using outbuf = basic_outbuf<false, char>; using outbuf_noexcept = basic_outbuf<true, char>; That `NoExcept` template parameter is perhaps the controversial part. It is not present originally in my formatting library. Besides the destructor, `basic_outbuf` has only one virtual function: `recycle()`, and it is declared as `noexcept(NoExcept)`. This is the only effect the `NoExcept` template parameter has. All other functions are guaranteed not to throw. Hence, by taking a `outbuf_noexcept&` parameter, a function states that the destination must not throw. That might be particularly good if such object comes from another module and we must avoid exceptions crossing modules boundaries. On the other hand, if a function takes an `outbuf&`, then it also accepts `outbuf_noexcept&`, because `basic_outbuf<true, CharT>&` derives from `basic_outbuf<false, CharT>`. When using `string_maker` you can choose between the two kinds. `string_maker<true>` derives from `basic_outbuf<true, char>&`. So if any exception raises from its internal `std::string`, then it is caught by a try/catch(...) block, stored as an `exception_ptr` and rethrown by `finish()`. This has the undesirable effect of delaying its proper handling ( after all, we rather stop what's being doing as soon as possible when an error appears ). So I think the recommendation would be to use `string_maker<false>&` if possible, and `string_maker<true>&` only if necessary. The reason why I think it's controversial is that it makes `recycle()` violates the Lakos Rule. And although the Lakos Rule is not a requirement in boost (afaik), I was wondering whether this library could interest LEWG in future as well. Anyway, this whole noexcept idea is not a central part of this library and can it be removed. Now, the other topic is how to implement that `get_message` function, i.e., how to write into an `outbuf` object. One can use `puts` and `putc` functions to insert string and chars. One can also use `fmtlib` through an output iterator adapter. Or one can write directly in the buffer. But I will ask you to read the doc [3] for that. It's a quick read, quicker than this email. The repository is: https://github.com/robhz786/outbuf I would prefer it to be part of Boost.Core instead of being a standalone library, and also to remove the `outbuf` namespace. But that is up to you. Best regards, Roberto [1] The Stringify library: https://github.com/robhz786/stringify [2] The great performance of Stringify is mainly thanks to the design of outbuf ( named there as `output_buffer` ): https://robhz786.github.io/stringify/doc/html/benchmarks/benchmarks.html#be… [3] "Writing into and outbuf object" https://robhz786.github.io/outbuf/doc/html/index.html#boost_outbuf.overview…

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[Boost.MSM] Please, update master with changes from develop
by Deniz Bahadir 08 Oct '19

08 Oct '19

Hello world, I just stumbled across a compilation-error with the latest Boost release (1.71) of Boost.MSM for which I already provided a merge-request [1] a year ago, and which was merged to "develop" branch at that time, too. Still, the "master" branch lags this merge-request (and a lot more [2] from former years which are in "develop") but has some other unrelated merge-requests [3] merged in which are not in "develop". I would love seeing "develop" being merged into "master" (and maybe vise-versa) so that bugs for which fixes already exist will no longer be present in the next Boost release. Thanks for taking care of. Deniz [1] https://github.com/boostorg/msm/pull/15 [2] https://github.com/boostorg/msm/compare/master...develop [3] https://github.com/boostorg/msm/compare/develop...master

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[contract] new maintenance release for Boost 1.72
by Lorenzo Caminiti 07 Oct '19

07 Oct '19

Hello Release Managers & all, I made a maintenance release of Boost.Contract. All tests pass, docs are updated, etc. The code is up-to-date in boost/contract/master. Can you please pull changes from boost/contract/master into the upcoming Boost 1.72 release? These are the changes: * Using std::uncaught_exceptions on C++17 compilers onward (instead of the now obsolete std::uncaught_exception). * Fixed a few warnings. * Removed linking to Boost.System (Boost.System is now a header-only library). * Added this library to Boost's Continuous Integration (CI). * Fixed documentation typos. Thank you in advance. --Lorenzo

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git pull on Boost 'develop' branch problem
by Edward Diener 03 Oct '19

03 Oct '19

When I do a 'git pull' on Boost checked out to 'develop' it ends with: error: Server does not allow request for unadvertised object 3eb4826d1d2a3e46207a7e4a0467d9bab96d37f5 Anybody know why this is happening with the latest Boost in the 'develop' branch and if I need to do something to correct this ? It does not seem to b3e affecting anything, and it appears the 'git pull' is successful at the top level in pulling the latest 'develop' changes.

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Re: [boost] New JSON library from the maker of Beast!
by Bjorn Reese 30 Sep '19

30 Sep '19

On 9/30/19 12:14 PM, julien.blanc(a)tgcm.eu wrote: > Do you have an example of an efficient implementation of a pull parser on top of async io ? I find push parsers really more straightforward in that case. Vinicius has an HTTP pull parser here: https://github.com/BoostGSoC14/boost.http > Pull parsers can also be built on top of push parsers, although it is less easy. Indeed, that is how we implemented XmlTextReader in libxml2, and it was a rather painful experience. Coroutines can help, as Phil pointed out, but pull parser are also a natural fit for parser combinators (e.g. HTTP contains a partial URL syntax, so it could be created combining HTTP and URL pull parsers.) I am not sure how well coroutines would handle this case.

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Who is maintaining Boost.Random?
by Christoph Conrads 29 Sep '19

29 Sep '19

Last Tuesday I submitted a feature request for Boost.Random and received absolutely no feedback which seems to be unusual judging by last week's discussions (e.g. secure-by-default networking with Boost.Asio). Is anybody maintaining Boost.Random currently and if not, how can I proceed with my feature request? Christoph Conrads

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How to handle contributions from anonymous?
by Hans Dembinski 27 Sep '19

27 Sep '19

Hi all, I got a PR from a contributor who prefers to remain anonymous. The person created new files and instead of putting a real name, the person added just initials. I am talking to the person to see whether they can be convinced to give a real name. Any advice on how to handle this? My feeling is that a copyright notice without a real name is illegal. I could publish the code in my name, but then a documented transfer of copyright from the contributor to me is missing, which then puts me in a vulnerable position. Any thoughts? Best regards, Hans

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MS STL now open source (and using Boost)
by John Maddock 26 Sep '19

26 Sep '19

Microsoft's standard library is now in the process of going open source (the code is there, but not the tests yet), see : https://devblogs.microsoft.com/cppblog/open-sourcing-msvcs-stl/ Interestingly they're using the Math library's special functions en-mass for enhanced <cmath> support, and a quick grep of the code turns up other references to Boost, though I haven't identified the libraries they've borrowed from yet. Hopefully this means that in the long turn we'll see patches and enhancements flowing in both directions for the benefit of all. John. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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more (hyper)complex types
by Gero Peterhoff 26 Sep '19

26 Sep '19

Hallo Developers, Hello John, I'm missing the (hyper)complex types in boost::math: - dual, i²=0 https://en.wikipedia.org/wiki/Dual_number - acomplex (anormal complex), i²=1 https://en.wikipedia.org/wiki/Split-complex_number - sedenion, https://en.wikipedia.org/wiki/Sedenion and the arithmetic functions for this types. Can you provide it? That would be great! thx Gero

3 2

Memory leak in add_options
by Vinitha Anish(UST,IN) 24 Sep '19

24 Sep '19

Hi , Our static analyzer report an memory leak with add_options . We use namespace po = boost::program_options; po::options_description desc("Options"); desc.add_options() ("name", po::value<std::string>(), ...) // add option ; The issue reported in boost library file value_semantic.hpp:199 template<class T> typed_value<T>* value(T* v) { typed_value<T>* r = new typed_value<T>(v); return r; } memory is dynamically allocated here and return at line 201. Can anyone suggest how do we handle this memory leak.

1 0

How to bind boost::asio::ip::tcp::socket to a local endpoint with a sperific local IP address?
by JH 24 Sep '19

24 Sep '19

Hi, I have searched the documents, but still could not clarify how to bind the socket to a local IP address, which API could I add my local IP address to it? socket.bind(boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), 12345)); ....... boost::asio::ip::tcp::resolver::query query(remoteServerIPAddress, portNumber); Thank you. Kind regards, - jh

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