July 2013 - Boost - lists.preview.boost.org

[unordered] a strange limitation for move emulation in Boost.Unordered
by Joaquin M Lopez Munoz 08 Jul '13

08 Jul '13

Here: http://www.boost.org/doc/html/unordered/compliance.html#unordered.complianc… it reads: "Non-copyable objects can be stored in the containers, but without support for rvalue references the container will not be movable." Why not? Container movement does not ever touch its elements, so I don't see the connection. Joaquín M López Muñoz Telefónica Digital

2 5

boost-1.54 needs a bugfix!
by Oliver Kowalke 08 Jul '13

08 Jul '13

unfortunately boost-1.54 needs a bugfix - because my request to merge boost.coroutine into release a required bugfix was not applied :( I'm wondering because the regression-tests are passed?! what to do? should I modify the fix in boost-release and archives of boost-1.54 are rebuild?

11 24

[fusion] Adapter for std::array
by Mateusz Loskot 07 Jul '13

07 Jul '13

Hi, I have prototyped Fusion adapter for std::array, as an attempt to clear the related feature request: https://svn.boost.org/trac/boost/ticket/8241 Here is the functional and testable code of the adaptor : https://github.com/mloskot/boost_fusion_std_array I will appreciate any critique and comments. Unfortunately, I have hit the apparently well-known problem. It is the Fusion begin/end ADL issues with C++0x range-based for and such, as discussed and reported here: http://lists.boost.org/Archives/boost/2010/12/174199.php https://svn.boost.org/trac/boost/ticket/4028 There has been no feedback to the ticket #8241, so I'm not sure what is the Fusion authors' view on std::array adoption. So, a couple of questions: Do the Fusion authors consider any cure for the ADL issues? If not, despite the inconvenience of use of qualified names, would it be still possible to accept std::array into Fusion? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

4 7

Interest in a 'Boost.property' library?
by Metodi Todorov 07 Jul '13

07 Jul '13

Is there any interest of "C# property" like library? struct vec2 { float get_x() const{...} float set_x() const{...} ... property_rw<float, vec2, &vec2::get_x, &vec2::set_x> x; vec2() : y(this) {} }; vec2 v; v.x = 15.0f; cout << v.x << endl; Example: http://sourceforge.net/projects/cproperty/?source=dlp Regards, Metodi Todorov

5 5

Benchmarking for performance?
by Arpan Sen 07 Jul '13

07 Jul '13

Hi Boost Dev, What sort of benchmarking does the community do for performance when moving from one revision to another? Kind of regression numbers for benchmark tests I would say for memory and time required. Does not have to be at an application level - even at a data structure level is a good start. Thanks a lot. Arpan

1 0

Historic of regression tests?
by Joaquin M Lopez Munoz 07 Jul '13

07 Jul '13

The regression tests at http://www.boost.org/development/tests/release/developer/summary.html are constantly updated (of course), but I seem to remember that the version manager used to backup a snapshot of this at each release. Am I right (I found nothing searching through boost.org)? Is there some sort of historic info on regression tests? Thank you, Joaquín M López Muñoz Telefónica Digital

2 1

[log] Setup Windows event log backends
by Renato Forti 06 Jul '13

06 Jul '13

Hi, I am trying setup a basic: <http://www.boost.org/doc/libs/1_54_0/libs/log/doc/html/log/detailed/sink_ba ckends.html#log.detailed.sink_backends.event_log> Windows event log, and I copy and past code from log documentation. My app link with: 1> main.cpp 1> Linking to lib file: boost_filesystem-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_system-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_log-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_thread-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_log_setup-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_date_time-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_chrono-vc110-mt-gd-1_54.lib But I have some link problems: 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::basic_si mple_event_log_backend<char>(void)" (__imp_??0?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAE@ XZ) referenced in function "class boost::shared_ptr<class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> > __cdecl boost::make_shared<class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> >(void)" (??$make_shared@V?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boos t@@@boost@@YA?AV?$shared_ptr@V?$basic_simple_event_log_backend@D@sinks@v2_mt _nt5@log@boost@@@0@XZ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::~basic_s imple_event_log_backend<char>(void)" (__imp_??1?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAE@ XZ) referenced in function "public: void * __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::`scalar deleting destructor'(unsigned int)" (??_G?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAEPAXI@Z ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::set_even t_type_mapper(class boost::log::v2_mt_nt5::aux::light_function<enum boost::log::v2_mt_nt5::sinks::event_log::event_type __cdecl(class boost::log::v2_mt_nt5::record_view const &)> const &)" (__imp_?set_event_type_mapper@?$basic_simple_event_log_backend@D@sinks@v2_mt _nt5@log@boost@@QAEXABV?$light_function@$$A6A?AW4event_type@event_log@sinks@ v2_mt_nt5@log@boost@@ABVrecord_view@456@@Z@aux@345@@Z) referenced in function "void __cdecl init_logging(void)" (?init_logging@@YAXXZ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::consume( class boost::log::v2_mt_nt5::record_view const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (__imp_?consume@?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost @@QAEXABVrecord_view@345@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocat or@D@2@@std@@@Z) referenced in function "protected: void __thiscall boost::log::v2_mt_nt5::sinks::basic_formatting_sink_frontend<char>::feed_rec ord<class boost::log::v2_mt_nt5::aux::fake_mutex,class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> >(class boost::log::v2_mt_nt5::record_view const &,class boost::log::v2_mt_nt5::aux::fake_mutex &,class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> &)" (??$feed_record@Vfake_mutex@aux@v2_mt_nt5@log@boost@@V?$basic_simple_event_l og_backend@D@sinks@345@@?$basic_formatting_sink_frontend@D@sinks@v2_mt_nt5@l og@boost@@IAEXABVrecord_view@234@AAVfake_mutex@aux@234@AAV?$basic_simple_eve nt_log_backend@D@1234@@Z) What is wrong? Thanks

3 10

[log] Build fail : log (1.44.0) on vc 11 using cxxflags=-Zc:wchar_t-
by Renato Forti 05 Jul '13

05 Jul '13

Hi All, I need use cxxflags=-Zc:wchar_t-, because I will use boost with my QT project! I build boost like this (debug in this case): bjam toolset=msvc-11.0 variant=debug threading=multi link=shared cxxflags=-Zc:wchar_t- But log lib fail with this: call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-mul ti\formatter_parser.obj.rsp" ...failed compile-c-c++ ..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading -multi\formatter_parser.obj... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.dll for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.lib for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.pdb for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...failed updating 4 targets... ...skipped 6 targets... Anyone can helpeme? Thanks

3 6

gmp-5.1.2 / boost-1.54 / multiprecision lib
by Fred Schneider 05 Jul '13

05 Jul '13

Hello, I'm a bit of a newbie and I ran into some issues using gmp with boost. After building gmp-5.1.2, I tried to build a simple file: boostMathExample.cpp, based on the documentation (using the multiprecision library + referencing gmp): ////////////////////////////////////////// #include <boost/multiprecision/gmp.hpp> using namespace boost::multiprecision; int main(int argc, const char *argv[]) { mpz_int v = 1; // Do some arithmetic: for (unsigned int i = 1; i <= 1000; ++i) v *= i; std::cout << v << std::endl; } /////////////////////////////////////////////// I received the following missing symbol errors when trying to build: g++ -I ~/Dev/C++/gmp-5.1.2 -I ~/Dev/C++/boost boostMathExample.cpp -O2 -o boostMathExample Undefined symbols: "_main", referenced from: start in crt1.10.6.o "___gmpz_init", referenced from: __static_initialization_and_destruction_0(int, int)in cccOFSnR.o __static_initialization_and_destruction_0(int, int)in cccOFSnR.o "___gmpz_clear", referenced from: ___tcf_1 in cccOFSnR.o __static_initialization_and_destruction_0(int, int)in cccOFSnR.o "___gmpz_set_si", referenced from: __static_initialization_and_destruction_0(int, int)in cccOFSnR.o ld: symbol(s) not found collect2: ld returned 1 exit status ======================================== I'm running the following version of g++: i686-apple-darwin10-g++-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5666) (dot 3) I configured gmp, version 5.1.2 with the following flags: ./configure --enable-cxx CXX=g++ CXXFLAGS=-O2 CC=g++ CFLAGS="-g -O2" and then ran "make" and "make check". Any insight would be appreciated. Thanks, Fred

3 3

[algorithm][minmax_element] implementation question
by Michael Marcin 04 Jul '13

04 Jul '13

I was looking at minmax_elemement to try and understand the algorithm. I noticed that the boost implementation looks significantly more complicated than the clang libc++ implementation. Mainly due to the potential_min_result variable that exists in the boost version. Is there a reason for this discrepancy? Is there a bug in the clang implementation? http://llvm.org/svn/llvm-project/libcxx/trunk/include/algorithm http://www.boost.org/doc/libs/1_54_0/boost/algorithm/minmax_element.hpp

3 2