November 2015 - Boost - lists.boost.org

A GUI Library
by jinhao 09 Nov '17

09 Nov '17

Hi, all I am developing a GUI library, it takes aim at easy-to-use and portable library for modern C++ methods. The project at http://stdex.sourceforge.net A git repository at http://nanapro.codeplex.com A brief at http://nanaproject.wordpress.com/2011/12/16/preliminary-study-of-nana-c-lib… Is there any interest in this library? Regards Jinhao

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Re: [boost] Boost CRC maintainer (Daryle Walker) missing in action?
by Olaf van der Spek 19 Jun '17

19 Jun '17

Hi Daryle, Any luck on your new setup? Gr, Olaf On Mon, Nov 28, 2011 at 1:11 AM, Daryle Walker <darylew(a)gmail.com> wrote: > I can look at it once I've finished my new setup. > > I had to reset my computer after a partial crash years ago. I never > got around to recreating my programming setup. My computer had been > at its maximum Operating System level back then, which is now 3 > versions behind. For the past few months, I've had my sister's old > laptop, with Windows Vista, and am trying to add a programming setup > to it now. > > > On Tue, Nov 22, 2011 at 7:18 AM, Beman Dawes <bdawes(a)acm.org> wrote: >> Hi Daryle, >> >> This guy has volunteered to take over maintenance of Boost CRC. Should >> we take him up on his offer? > >> ---------- Forwarded message ---------- >> From: >> Date: Wed, Nov 2, 2011 at 7:51 AM >> Subject: [boost] Boost CRC maintainer (Daryle Walker) missing in action? >> To: boost(a)lists.boost.org >> >> >> Hi, >> >> It looks like the Boost CRC maintainer (Daryle Walker) is missing in action? >> >> No response to tickets from the past 3 years. What's the procedure in this case? >> >> https://svn.boost.org/trac/boost/ticket/2492 >> https://svn.boost.org/trac/boost/query?component=crc&col=id&col=summary&col… > > -- > Daryle Walker > Mac, Internet, and Video Game Junkie > darylew AT gmail DOT com -- Olaf

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[container] moving a pre-built vector into a flat_set
by Sam Kellett 12 Mar '17

12 Mar '17

a common problem i encounter is that i have two stage's w/r/t to a large collection of data: building and querying. vector is obviously the king of building. flat_set is the king of querying. so what i often tend to do is build up a very large vector, sort it then create a flat_set using the flat_set(ordered_unique_t) constructor. however this still copies the entire vector into the flat_set, right? what i would like to be able to do is move the vector straight into the flat_set, something like: std::vector<T> data; flat_set data_set1(std::move(data)) // move vector in and sort it // or: std::sort(data.begin(), data.end()); // sort vector flat_set data_set2(ordered_unique_t, std::move(data)) // and move it in is this doable (am i just being blind?) or is there plans/interest for this?

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bad include guards
by Steven Watanabe 26 Jan '17

26 Jan '17

AMDG The following pairs of files have identical include guards ./boost/concept_check/general.hpp ./boost/concept/detail/msvc.hpp ./boost/concept_check/msvc.hpp ./boost/concept/detail/msvc.hpp ./boost/filesystem/cerrno.hpp ./boost/cerrno.hpp ./boost/interprocess/containers/tree.hpp ./boost/interprocess/containers/detail/tree.hpp ./boost/mpl/min_max.hpp ./boost/mpl/max.hpp ./boost/mpl/vector/aux_/front.hpp ./boost/mpl/list/aux_/front.hpp ./boost/multi_index/identity_fwd.hpp ./boost/multi_index/identity.hpp ./boost/python/pointee.hpp ./boost/python/detail/pointee.hpp ./boost/spirit/phoenix/closures.hpp ./boost/lambda/closures.hpp ./boost/xpressive/proto/v1_/proto_typeof.hpp ./boost/xpressive/proto/proto_typeof.hpp ./libs/config/test/boost_no_dep_nested_class.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/config/test/boost_no_mem_templates.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/config/test/boost_no_std_allocator.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/conversion/test.hpp ./libs/any/test.hpp ./libs/interprocess/example/print_container.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/interprocess/test/expand_bwd_test_template.hpp ./libs/interprocess/test/allocation_test_template.hpp ./libs/interprocess/test/printcontainer.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/interprocess/test/print_container.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/iostreams/test/detail/utf8_codecvt_facet.hpp ./boost/detail/utf8_codecvt_facet.hpp ./libs/regex/test/regress/test_regex_search.hpp ./libs/regex/test/regress/test_partial_match.hpp ./libs/serialization/test/C.hpp ./libs/serialization/test/A.hpp ./libs/xpressive/perf/regex_comparison.hpp ./libs/regex/performance/regex_comparison.hpp ./tools/inspect/time_string.hpp ./tools/common/time_string.hpp In Christ, Steven Watanabe

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[config] RFC PR 82
by Domagoj Saric 01 Aug '16

01 Aug '16

Hi everyone, I am finally getting back to (trying to) contributing some of my personal projects to Boost. For two of those, Err (https://github.com/psiha/err) and especially Functonoid (a C++11 generalization and rewrite of my previous Boost.Function related work) I need some lower level codegen and/or optimiser control functionality (i.e. portable macros wrapping toolset specific attributes and pragmas) that I've added to my personal fork of Boost.Config and which I've now submitted in the subject PR (https://github.com/boostorg/config/pull/82) I don't expect this PR to be accepted as is/'just like that' so I'm opening this thread where we can discuss which of those changes/macros are welcome, which need more work and which, for some reason, should not be part of Boost.Config (and which, in turn then, I have to move to some 'internal implementation headers' in libraries that will need them). To avoid 'spamming' (and save time;) I'll skip the explanation of the individual macros as I expect them to mostly be self-explanatory (if not from their name then from the minimal Boost.Config documentation additions that are part of th PR). ps. I'll be on the (off) road for the next three weeks so I don't know when I'll be able to respond until I get back... -- "What Huxley teaches is that in the age of advanced technology, spiritual devastation is more likely to come from an enemy with a smiling face than from one whose countenance exudes suspicion and hate." Neil Postman

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[Fit] pipable order of the arguments
by Vicente J. Botet Escriba 05 Mar '16

05 Mar '16

Hi, I would like to know what other think about the order of the pipe (See this issue https://github.com/pfultz2/Fit/issues/5) What would be the expected meaning of auto r1 =1 | pipable(f)(2); f(1,2) or f(2,1)? What would be the expected meaning of auto f2 = partial(f)(2); auto r1 =1 | pipable(f2); f(1,2) or f(2,1)? As the operator| has left-to-right associativity, we can not do auto x = 1 | 2 | pipable(f); We would need a way to pack the parameters auto x = forward_as_tuple(1, 2) | pipable(f); but this wouldn't compile as f has two parameters. or use parenthesis auto x = 1 | (2 | pipable(f)); and the result will be f(2, 1). Any ideas? Best, Vicente Vicente

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[regression] Winapi submodule tests missing
by Andrey Semashev 13 Feb '16

13 Feb '16

Hi, The winapi submodule tests are missing from the test matrix, although the status/Jamfile.v2 lists it. This is both on develop and master. Is there something I should do to make the tests appear?

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[err] RFC
by Domagoj Saric 11 Jan '16

11 Jan '16

https://github.com/psiha/err README.md copy-paste: --------------------------------------------- err - yet another take on C++ error handling. We have throw and std::error_code, what more could one possibly want? --------------------------------------------- std::error_code&co tried to solve or at least alleviate the problem of overhead of using exceptions (in terms of both source code verbosity and binary code size&speed) with functions which need to report failures that need not be 'exceptional' depending on the context of the call (thereby requiring try-catch blocks that convert exceptions to 'result codes'). Unfortunately, the way it was finally implemented, std::error_code did not quite accomplish what it set out to do: • in terms of runtime efficiency: 'manual'/explicit EH (try-catch blocks) is no longer needed but the compiler still has to insert hidden EH as it has to treat the functions in question as still possibly throwing (in fact the implementation/codegen of functions which use std::error_code for error reporting becomes even fatter because it has to contain both return-on-error paths and handle exceptions) • in terms of source code verbosity: again, try-catch blocks are gone but separate error_code objects have to be declared and passed to the desired function. Enter boost::err: 'result objects' (as opposed to just result or error codes) which can be examined and branched upon (like with traditional result codes) or left unexamined to self-throw if they contain a failure result (i.e. unlike traditional result codes, they cannot be accidentally ignored). Thanks to latest C++ language features (such as r-value member function overloads) incorrect usage (that could otherwise for example lead to a result object destructor throwing during a stack-unwind) can be disallowed/detected at compile time. Discussions where the concept (or a similar one) was first concieved of and/or so far discussed: • http://boost.2283326.n4.nabble.com/system-filesystem-v3-Question-about-erro… • http://cpptips.com/fallible • https://github.com/ptal/std-expected-proposal • https://github.com/ptal/expected • https://github.com/adityaramesh/ccbase/blob/master/include/ccbase/error/exp… • http://stackoverflow.com/questions/14923346/how-would-you-use-alexandrescus… • https://svn.boost.org/trac/boost/wiki/BestPracticeHandbook#a8.DESIGN:Strong… • http://2013.cppnow.org/session/non-allocating-stdfuturepromise **************************************************************** For starter's, to reduce the length of the first post, I'll assume that everyone as at least somewhat familiar with similar/related proposals from Andrei Alexandrescu (std::expected) and Niall Douglas (std::monad) to which I gave links above. What, primarily, makes (Boost.)Err different from other proposals is the ability to (using latest C++ features) detect/distinguish between temporaries and 'saved' return values by using two different class templates (result wrappers), fallible_result (for rvalues) and result_or_error (for lvalues) and thus minimise or often completely eliminate any extra verbosity: If we had a function foo() that produces bar_t objects but can fail with an err_t, up till now we had two options: * bar_t foo() throw( err_t ); * optional<bar_t> foo( err_t & ); Err enables the library writer to write a single API and a single implementation: err::fallible_result<bar_t, err_t> foo(); where fallible_result is the class template that wraps temporaries/rvalues returned from functions and its member functions are all declared with && (i.e. callable only on rvalues) so you get a compiler error if you save it to an auto value and try to do anything with it. The two exceptions are the implicit conversion operators to: - bar_t, which will either return bar_t or throw err_t and which is used for the 'EH code path' bar_t my_bar( foo() ); - err::result_or_error<bar_t, err_t> which is used for the 'oldsk00l nothrow error code path' err::result_or_error<bar_t, err_t> maybe_bar( foo ); if ( maybe_bar ) { print( *maybe_bar ); } else { log( maybe_bar.error() ); } Also, if the fallible_result rvalue is left uninspected and contains an error its destructor will throw (which AFAICT should be safe considering it is an rvalue and no other exception can possibly be active at the same time) - this makes code that uses Err enabled libraries/APIs but relies on EH almost indistinguishable from 'classic EH' APIs (almost because the one difference that remains is with the immediate use of the return value: because of the wrapper class one can no longer write foo().do_something() but has to implicitly use the -> operator and write foo()->do_something() where the -> operator will check-and-throw if foo() did not succeed). To wrap up, this approach gives the user the immediate and fine grained control over which error handling mechanism he/she wants to use while allowing the developer to write a single API and implementation - AFAICT it is a no brainer replacement for <system_error>, it is less verbose and much more efficient ;-) ps. the small library @ https://github.com/psiha/err is by no means a finished product, it contains no tests or documentation but 'it works' (i.e. it is used in the, also upcoming, https://github.com/psiha/mmap)...I'm bringing it to public view for scrutiny, discussion and guidance lest I steer in the wrong direction ;) -- "What Huxley teaches is that in the age of advanced technology, spiritual devastation is more likely to come from an enemy with a smiling face than from one whose countenance exudes suspicion and hate." Neil Postman

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Problems building Boost libraries for Windows Store when C++/CX is involved
by Mikael Olenfalk 04 Jan '16

04 Jan '16

Hi, I am working on porting the boost libraries we depend on to winrt, most porting is rather straightforward (basically switch from win32 apis which are 20 years old to apis which are 15 years old :D ). However I have hit a bit of a problem when compiling Boost.Log. Boost.Log depends on Boost.Asio which uses C++/CX to call some of the newer Store APIs (Windows::Networking and friends). When I build I get these errors: compile-c-c++ ..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj dump_ssse3.cpp ..\..\..\libs\log\src\dump_ssse3.cpp: fatal error C1107: could not find assembly 'platform.winmd': please specify the assembly search path using /AI or by setting the LIBPATH environment variable call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" x86 store >nul cl /Zm800 /ZW /EHsc -nologo @"..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj.rsp" (As you can see I have monkey-patched msvc.jam to append the "store" argument to vcvarsall.bat - to no avail :( -- the monkey-patch is here if you want to look at it: https://github.com/mauve/build/commits/universal-windows-boost-1.59.0 ) The @response file looks like this: "..\..\..\libs\log\src\dump_ssse3.cpp" -Fo"..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj" -TP /Z7 /Od /Ob0 /W3 /GR /MDd /Zc:forScope /Zc:wchar_t /wd4675 /EHs /arch:SSE2 /bigobj /wd4003 /wd4456 /wd4459 /wd4503 -c -DBOOST_ALL_NO_LIB=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_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_USE_DLL=1 -DDATE_TIME_INLINE -DWINAPI_FAMILY=WINAPI_FAMILY_APP -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_WIN32_WINNT=0x0603 "-I..\..\.." Regards, Mikael

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[multiprecision] uses boost::math::gcd without including the header
by Peter Dimov 04 Jan '16

04 Jan '16

include/boost/multiprecision/cpp_int/misc.hpp uses boost::math::gcd (and lcm), but does not include common_factor_rt.hpp.

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Status of the CMake-ification
by Louis Dionne 02 Jan '16

02 Jan '16

Dear Boost, I'd like to inquire about the status of the CMake-ification of Boost that had been started a while ago. AFAICT, the effort is completely stopped now; is this correct? Also, I'd like to poll the community to gauge interest in the rebirth of such an effort. __I'm not proposing myself to work on such a rebirth__, but I'm just curious to know what the community thinks about it. I, for one, would love to see it happen. Regards, Louis -- View this message in context: http://boost.2283326.n4.nabble.com/Status-of-the-CMake-ification-tp4681599.… Sent from the Boost - Dev mailing list archive at Nabble.com.

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[smart_ptr] Moving cast for unique_ptr
by Karolin Varner 21 Dec '15

21 Dec '15

Hi all! There is the family of boost pointer cast (boost::static_pointer_cast, boost::dynamic_pointer_cast, ...) that allow a developer to write generic code by casting pointers regardless of whether they are some smart pointer (e.g. shared_ptr) or plain pointers. However, those functions have not been implemented for unique_ptr, because they create a copy of their pointer and unique_pointers can not be copied. In my case I still needed to cast some unique_ptr and since it's ok to move unique_ptrs I wrote a function that does exactly that. The code is below – Comments are very, very welcome. It works for my case, but I am sure it is not as generic and safe as it should be ;) . Specifically, for a library, it should be made to work on any kind of smart/plain pointer. Not just unique_ptr. Is there any interest to include a boost::static_moving_pointer_cast and the other types of casts in boost? Best, Karolin /// Dynamic cast a unique_ptr. /// /// This function shall move the pointer in in_ptr, into /// a new unique_pointer of the desire type, dynamic_casting /// it in the process. /// In given pointer shall contain a NULL pointer afterwards. /// /// If unsuccessful, function shall throw an error and leave /// in_ptr unmodified. /// /// This behaviour contrasts a bit with the behaviour of the /// normal dynamic_cast: /// 1. dynamic_cast copies objects, this moves them since /// unique_pointers can not be copied. /// 2. dynamic_cast returns a NULL pointer if the pointer to /// cast is of an incomplete type, this throws /// incomplete_cast instead, to ease error handling. /// /// @tparam T The type to convert to (as non-pointer) /// @tparam F The type to convert from (as non-pointer) /// @param in_ptr The unique_ptr to cast /// @return in_ptr, cast to the desired type template<typename T, typename F> std::unique_ptr<T> dynamic_moving_pointer_cast(std::unique_ptr<F> &in_ptr) { // Exception safety: If The dynamic cast throws an error, // or of we throw incomplete_cast, in_ptr will still be // unmodified T *plain_out_ptr = dynamic_cast<F*>(in_ptr.get()); if (plain_out_ptr == NULL && in_ptr.get() != NULL) throw incomplete_cast(); // Exception safety: Both operations are noexcept in_ptr.release(); return std::unique_ptr<T>(plain_out_ptr); }

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[variant] Opinion on boost::safe_get<> and default boost::get<> behavior
by Antony Polukhin 18 Dec '15

18 Dec '15

Hi all, I'm in doubt and would like to hear opinions on the following issue. boost::get for boost::variant was not making any compile time checks, resulting in runtime errors where a compile time error must be: boost::variant<int, string> v(100); boost::get<bool>(&v); // returns NULL instead of compile time error boost::get<bool>(v); // throws exception on runtime instead of compile time error Now we have an implementation of compile time checked get in a separate branch at git: boost::variant<int, string> v(100); boost::safe_get<bool>(&v); // compile time error boost::safe_get<bool>(v); // compile time error boost::unsafe_get<bool>(&v); // returns NULL instead of compile time error boost::unsafe_get<bool>(v); // throws exception on runtime instead of compile time error I'm in doubt, what the default behavior of boost::get must be: * safe_get behavior is much closer to Standard Library behavior (just like std::get for tuples) and allows to avoid errors in user code * unsafe_get behavior is same as behavior of old boost::get and won't break user's code if boost::get is used in some generic contexs What's your opinion? -- Best regards, Antony Polukhin

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[LOG] formatting_ostream API change
by Andrew Hundt 09 Dec '15

09 Dec '15

I had the following code, which worked in 1.58: #include <boost/log/trivial.hpp> #include <boost/exception/all.hpp> #include <boost/algorithm/string.hpp> /// @todo move elsewhere, because it will conflict with others' implementations of outputting vectors template<typename T> inline boost::log::formatting_ostream& operator<<(boost::log:: formatting_ostream& out, std::vector<T>& v) { out << "["; size_t last = v.size() - 1; for(size_t i = 0; i < v.size(); ++i) { out << v[i]; if (i != last) out << ", "; } out << "]"; return out; } I used it to output a std::vector<float> as follows: BOOST_LOG_TRIVIAL(trace) << “Real joint angles from FRI: " << realJointPosition << "\n"; However this now seems to fail in 1.59. I’ve created a github gist with the compiler output <https://gist.github.com/ahundt/5869dbd09e889b7153c3> in case that’s helpful as well. I see that the update recently had some breaking changes, what is the new way to provide the desired functionality? Thanks for your help. Cheers! Andrew Hundt

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interest in an asynchronous linear algebra library?
by Oswin Krause 07 Dec '15

07 Dec '15

Hi list, Disclaimer: What I am proposing here does not exist (yet). But it will in the near future and if there is interest i would like to give something back to the boost community. I would like to propose a new library to boost: asynchronous blas. What is it and what can I do with it? It is a linear algebra library where all computations are carried out in an asynchronous manner on GPU and CPU. Computing a matrix-matrix product does not block the current thread but instead launches a task which at some point returns with a result, allowing the main thread to continue until the result is needed. GPU and CPU tasks can be started at the same time depending on each other (e.g. a CPU computation waits until the GPU returned some needed result and vice-versa) Why is this important? Which problems does it solve? Many linear algebra libraries are target towards either a) solving a few large linear algebra problems b) solving many small similar problems This library is targeted towards the middle ground: a medium amount of decently sized problems. Here the problem is that it is often hard to use all the computing resources available as a single problem will not exhaust the device resources and there is no easy way to launch several similar tasks in parallel. This problem occurs often in GPU computing where out-of-order execution of kernels is used to fill up the device. Similarly, it is often hard to make CPU and GPU work together as GPU tasks are asynchronous while CPU tasks are often synchronous and it is not straight forward to couple both without blocking either CPU or GPU. How does it work? Expression templates similar to boost::ublas are used to create a dependency graph: which object is used in which computations and which tasks have to wait to ensure a correct outcome? a simple case would be two independent computations like matrix A=prod(B,trans(B)); matrix C=prod(trans(B),B); a normal library like ublas would wait until A is computed before C is evaluated. Instead, it can be more efficient to just add the two tasks to a list and let worker threads execute them as soon as resources are available. First the computation of A is put into the graph and A is marked as "being written to" while B is marked as "being read". When C is added to the list, it does not depend on the first computation as several tasks can read from B at the same time. So another worker thread can grab the task and execute it. If we now add the task B += prod(D,prod(C,trans(D)); the library computes it as matrix temp = prod(C,trans(D); B += prod(D,temp). temp can be computed as soon as C is computed. But B can only be computed after A and temp are computed as we can only write to B after all previous tasks using B are finished. Are you qualified? I am main contributor to https://github.com/Shark-ML/Shark/ and as part of it I forked ublas https://github.com/Shark-ML/Shark/tree/master/include/shark/LinAlg/BLAS which now uses several linear algebra libraries as possible backends (ATLAS, openBLAS...). What is the timeline? I would start developing a minimal example ASAP based on the rewrite of ublas above. I would use a minimum set of features (only dense square matrices) and basic GPU support. Opinions? Best, Oswin

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Boost 1.60.0 beta 1 Release Candidate 2 available for testing
by Marshall Clow 04 Dec '15

04 Dec '15

Release candidate files for 1.60.0 beta 1 are available at http://boost.cowic.de/rc/ 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. This helps ensure the candidates build OK before we push them out to SourceForge. Changes since rc1: * Boost.Sprit has been updated and Boost.Log now builds. * Boost.Math has been updated and now builds. Known issues: * Errors when building libraries for visual studio: test and type_erasure. * Boost.Test fails when building on Darwin with gcc 4.9.2 The files (and associated md5s) are: MD5 (boost_1_60_0_b1_rc2.7z) = dd38daa9378a6002fc12da0cab695511 MD5 (boost_1_60_0_b1_rc2.tar.bz2) = f3c9ffc14db3b2e55c7c5c703e69883d MD5 (boost_1_60_0_b1_rc2.tar.gz) = 89365262443cc16990b69f8e4b8b47ab MD5 (boost_1_60_0_b1_rc2.zip) = 3389bd4595a989fe95966440cbe45ca9 Thanks! -- The release managers

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compilation errors with ublas / cppad
by Peter Caspers 30 Nov '15

30 Nov '15

Hi, I think this has been asked before, but since I am not aware of any answer, I would like to bring up the topic again: When using CppAD::AD<double> with boost ublas, certain compilation errors show up. I attach a small example (ublas_cppad.cpp) and the (start of the) error messages I get (compilation_errors.txt, produced with boost 1.59.0, g++ 4.9.3, CppAD-20151124). The problem is in matrix_assign.hpp; when changing template<class E1, class E2, class S> BOOST_UBLAS_INLINE bool equals (const matrix_expression<E1> &e1, const matrix_expression<E2> &e2, S epsilon, S min_norm) { return norm_inf (e1 - e2) < epsilon * std::max<S> (std::max<S> (norm_inf (e1), norm_inf (e2)), min_norm); } to template<class E1, class E2, class S> BOOST_UBLAS_INLINE bool equals (const matrix_expression<E1> &e1, const matrix_expression<E2> &e2, S epsilon, S min_norm) { S tmp = norm_inf (e1 - e2); return tmp < epsilon * std::max<S> (std::max<S> (norm_inf (e1), norm_inf (e2)), min_norm); } the example code compiles without errors. Can someone point out, how this should be fixed (either on boost or CppAD side)? In general, are there requirements for a type T to cooperate with ublas matrices one should be aware of? Thank you Peter

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Is master branch open for bug fixes?
by Vicente J. Botet Escriba 30 Nov '15

30 Nov '15

Hi, the calendar says that master branch is open for bug fixes, but not mail has been sent to to notify it. Could some release manager confirm that? Best, Vicente

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[program_options] empty string argument
by Benedek Thaler 30 Nov '15

30 Nov '15

Hi, I have the exact same problem: http://boost.2283326.n4.nabble.com/ProgramOptions-explicit-empty-string-arg… --compression '' gave me a specified, empty compression switch value, as expected, on boost 1.58. However, on 1.59, the empty string counts against the positional arguments, and causes regressions. Also, --compression='' gives: The argument for option '--compression' should follow immediately after the equal sign. What is the recommended workaround? Is it planned to be fixed/changed? Thanks, Benedek

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[Boost.LLVM] Synopsis now available
by Andy Jost 29 Nov '15

29 Nov '15

I've created a new GitHub repository for this project and uploaded a synopsis of the proposed interface. I redesigned the interface, so it differs slightly from the prototype code and examples I gave before. Please take a look and provide feedback if you can! https://github.com/andyjost/Boost.LLVM/blob/master/boost_llvm.cpp -Andy

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Interest in an LLVM library?
by Andy Jost 26 Nov '15

26 Nov '15

Is there interest in an LLVM library? My motivation is to simplify the dynamic creation of functions, modules, and programs by defining an EDSL modeled after the C language. LLVM provides an API based exclusively on function calls that is verbose and difficult to use. The EDSL is more expressive and easier to use. (This may remind some people of Boost.Python and indeed these libraries are similar in motivation.) The scope of this proposal is limited. The proposed library does not compile, link, optimize, save, or load anything, for example, since the LLVM API is suitable for that. Also, it may not support obscure features, even if they seem to be within its purview, since one can always make direct calls to the LLVM API. I have written about 6500 lines of prototype code in the context of another project (a compiler for the language Curry, if anyone is interested). It is not a complete solution, but is by no means trivial, either. I'll discuss that next, but since the discussion is somewhat lengthy, let me first explain what I'm looking for by sending this. I think this EDSL would make a good Boost library. If others agree, then the next step is to review the design. I need second opinions and help from more knowledgeable people to improve the design. There are a few places in particular where I think a redesign is necessary. After that, I'm happy to implement the final library (and would gladly accept help, if anyone is interested). Now, I'll show a few examples and provide links to the prototype code. First, here's how to create a module and put it in scope: module const example_module("example"); scope _ = example_module; The scope object sets the insertion point for types, functions, and global variables. We can create a type as follows: type i32 = int_(32); i32 is a 32-bit integer. It is easy to build more complex types, e.g., i32[2] is an array type, *i32 is a pointer type, and i32(i32,i32) is a function type. An expression like i32(42) produces a constexpr. As you might guess at this point, the prototype makes heavy use of SFINAE. I've gone to a lot of effort to make this work with everything I can think of, particularly multi-dimensional arrays and initializer_lists. So, an expression like (i32[3][2])({{1,2,3},{4,5,6}}) works! (Note: i32[3][2] is the C++ type int32_t[2][3] because that's the only sensible way to interpret successive calls to operator[]). We can create a struct from a sequence of types like this: type foo = struct_("foo", {i32, *i32}); Or, we can leave out the sequence to get an opaque struct. A function prototype can be created as follows: function const f = extern_(i32(i32), "f", {"i"}); This function, f, takes an i32 (named "i") and returns an i32. The function is placed in example_module, since the code appears in its scope. There are two other linkage-specifying functions: static_ and inline_. extern_ and static_ are also used to create global variables (i.e., if the type is not a function). To define the body, we create another scope: { scope _ = f; // code for f. } To understand this, we have to discuss scopes in more depth. There are three nested levels of scope: the current module, the current function, and the current basic block. The code above sets the current function to f and the current basic block to f's entry point. Generally speaking, within a function body we write statements that generate instructions. Those instructions are inserted into the current function at the end of the current basic block. To define the body, we can declare values and operate on them. For example: value i = arg("i"); Here, "arg" is a special function that fetches the named function parameter. We can add instructions to f using operators or special methods. For example: value j = i + 1; return_(j); Branches manipulate the current basic block. Here's an if statement: label true_path, false_path; if_(i, true_path, false_path); { scope _ = true_path; // code for true. } /* else */ { scope _ = false_path; // code for false. } // new basic block here. This generates instructions to test i, take the appropriate branch, and then continue to a new basic block in the right places (which depends on whether the paths terminate with a branch instruction). It also updates the scope so that statements following if_() are inserted into the new basic block. Believe me when I say it is not trivial to do this with the LLVM API. Although it is sometimes necessary to pre-declare labels as shown above, we can usually employ C++11 lambdas to simplify the encoding: if_(i , []{ /* code for true */} , []{ /* code for false */ } ); The prototype code can be found under https://github.com/andyjost/Sprite-3/tree/master/include/sprite/backend. Also, there are many examples under https://github.com/andyjost/Sprite-3/tree/master/examples. Other parts of the Sprite-3 project are unrelated to this proposal. A good example to start with generates the Fibonacci numbers (https://github.com/andyjost/Sprite-3/blob/master/examples/fib.cpp) Here's the interesting part: // Create a new module and associate it with this lexical scope. module const fib_module("fib"); scope _ = fib_module; // Declare types. auto const char_ = types::char_(); auto const i32 = types::int_(32); auto const i64 = types::int_(64); // Declare external functions. auto const printf = extern_(i32(*char_, dots), "printf"); // Define the @fib function. auto const fib = extern_(i64(i64), "fib", {"n"}); { scope _ = fib; value n = arg("n"); if_(n <(signed_) (2), []{return_(1);}); return_(fib(n-2) + fib(n-1)); } // Define the @main function. auto const main = extern_(i32(), "main"); { scope _ = main; value const x = fib(5); printf("fib(5)=%d\n", x); return_(0); } After this code runs, fib_module contains an intermediate representation of the program. The LLVM API can be used to save that to disk, compile it to assembly, link in the C library (to get printf), or JIT compile any of the functions, among other things. Thanks to everyone who made it this far :) I'm looking forward to your feedback. -Andy

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[trippels-ppc64le][math] Missing quadmath.h errors
by Andrey Semashev 24 Nov '15

24 Nov '15

Hi, I'm seeing some test failures on the trippels-powerpc64le-gcc-6.0 tester that amount to Boost.Math failing to build because the quadmath.h header is missing. http://www.boost.org/development/tests/develop/developer/output/trippels-po… I understand that gcc 6.0 is an unreleased compiler, but the error is probably not a consequence of a compiler bug. Besides, another tester, Flast-FreeBSD10-gcc-6.0.0~gnu++11, passes. Is it possible that the header is not provided for powerpc64le? Or is an optional dependency whose presence is misdetected? Is this a known problem?

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[teeks99][test] Test failures on MSVC 8-11
by Andrey Semashev 23 Nov '15

23 Nov '15

Hi, I'm seeing massive Boost.Log test failures on teeks99 with MSVC versions 8 through 11. The links to the failure messages lead to Boost.Test but the console output is not helpful (shows a successful compilation of a source file [1]). I can see Boost.Test tests are also failing massively on these compilers. Could this be fixed? [1]: http://www.boost.org/development/tests/develop/developer/output/ teeks99-08d-win2012R2-64on64-boost-bin-v2-libs-log-test-attr_attribute_set- test-msvc-11-0-dbg-adrs-mdl-64-thrd-mlt.html

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[Config] boost::uint32_t != std::uint32_t on some targets
by Louis Dionne 23 Nov '15

23 Nov '15

Dear Boost, I recently fell into a trap where a program wouldn't compile because of a difference between `boost::uint32_t` and `std::uint32_t`. Specifically, I was trying to cross-compile from OS X to ARM, and the following program wouldn't compile #include <boost/cstdint.hpp> #include <cstdint> #include <type_traits> static_assert(std::is_same<std::uint32_t, boost::uint32_t>::value, ""); int main() { } I was building with arm-none-eabi-g++ -I /path/to/boost -std=c++11 -c main.cpp I have asked a question on StackOverflow [1], and I now understand why the two types are not required to be the same. However, I think it is a QOI issue that those two types are not the same, since it makes interoperating between `std::uint32_t` and `boost::uin32_t` more difficult. Is there a reason for this difference, and if not would it be reasonable to ensure that `boost::uint32_t == std::uint32_t` whenever the latter is defined, i.e. in C++11 and above? Regards, Louis [1]: http://stackoverflow.com/q/33857554/627587

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build and install boost subset does not install the header files
by George Georgiev 22 Nov '15

22 Nov '15

Hi, I am trying to use github boost to obtain a subset of the libraries. I found that using the following subset of modules allows me to build boost_system. git submodule update --init tools/build || exit 1 git submodule update --init tools/inspect || exit 1 git submodule update --init libs/assert || exit 1 git submodule update --init libs/config || exit 1 git submodule update --init libs/core || exit 1 git submodule update --init libs/predef || exit 1 git submodule update --init libs/system || exit 1 git submodule update --init libs/utility || exit 1 The problem is that ./b2 ... install does not copy the header files. Is this a bug that I am hitting? My commands are: ./bootstrap.sh --prefix=../../boost --includedir=../../boost/include || exit 1 PATH=$CLANGBIN:$PATH \ ./b2 \ toolset=clang \ cxxflags="-std=c++11 -stdlib=libc++ -isystem/Developer/SDKs/MacOSX10.7.sdk/usr/include" \ linkflags="-stdlib=libc++" \ install threading=multi link=static Thanks, -g

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