February 2015 - Boost-users - lists.preview.boost.org

[interprocess] Determine size of managed_shared_memory
by Kai Benndorf 12 Oct '19

12 Oct '19

Hi all, I want to create a managed_shared_memory in exactly the size I needed. Therefore I do something like this: size = sizeof( common_managed_shared_memory ); size += sizeof( MyClassInSharedMem ); managed_shared_memory segment(create_only, "name", size ); MyClassInSharedMem allocates itself some memory by segment->allocate(). I added this also to the size, but get a boost::interprocess::bad_alloc exception on allocating this additional memory. Are there some magic bytes I forgot to add? Many thanks in advance Kai

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[Range, Phoenix] What am I missing...
by Robert Jones 25 Apr '17

25 Apr '17

Hi Folks Can anyone explain the output of this program... #include <iostream> #include <boost/range/algorithm/copy.hpp> #include <boost/range/counting_range.hpp> #include <boost/range/adaptor/reversed.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/phoenix/core/argument.hpp> int f( int i ) { return i * 2; } int main( ) { using boost::adaptors::reversed; using boost::adaptors::transformed; using boost::counting_range; using boost::copy; using boost::phoenix::arg_names::_1; copy( counting_range( 1, 5 ) | reversed | transformed( f ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; copy( counting_range( 1, 5 ) | reversed | transformed( bind( f, _1 ) ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; } Which is... 8 6 4 2 1768406272 1768406272 1768406272 1768406272 I'm using Gcc 4.6.2 & Boost 1.53 Thx All.

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[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example. typename sc = boost::statechart; class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; }; class MyStateMachine; class StSource; class StTarget; class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } }; class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; }; Thanks, Christophe

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Re: [Boost-users] Crashing Issue
by swati upadhyaya 04 Nov '15

04 Nov '15

hi I am using like this where RunningThreads_ is vector containing boost thread object pointer(handler).I am using interrupt() for the interruption of thread interruption_point() catching that interruption then joining.everytime its crashing in join() for me but for others who have the same configuration its working fine all of us has windos 8. For me also it was working last week but this week the same piece of code is crashing. :( RunningThreads_[i].handle->interrupt(); RunningThreads_[i].handle->join(); delete RunningThreads_[i].handle; On Thu, Feb 5, 2015 at 9:31 AM, swati upadhyaya <swatiupadhyaya(a)gmail.com> wrote: > RunningThreads_[i].handle->interrupt(); > LOG4CPLUS_INFO(root, "Thread Interrupted for " << > RunningThreads_[i].app_name << " successful"); > RunningThreads_[i].handle->join(); > LOG4CPLUS_INFO(root, "Waiting for thread to exit " << > RunningThreads_[i].app_name << " successful"); > delete RunningThreads_[i].handle; > LOG4CPLUS_INFO(root, "Thread handle for " << > RunningThreads_[i].app_name << " successfully deleted"); > //RunningThreads_.erase(i); > > On Wed, Feb 4, 2015 at 12:10 AM, Vicente J. Botet Escriba < > vicente.botet(a)wanadoo.fr> wrote: > >> Le 03/02/15 09:10, swati upadhyaya a écrit : >> >> In my code join() timed_joined() is crashing, I am using these API >> after interrupt(),Same piece of code is working for others but in my system >> its crashing, >> Is there some dependency problem I am using >> Boost version: 1.55.0 >> OS: Windows 8 >> IDE: Visual Studio 2010 >> >> Hi, >> >> it could help if you post the example and the backtrace. >> >> Which version/OS/compiler use others for which this works? >> >> Vicente >> >> _______________________________________________ >> Boost-users mailing list >> Boost-users(a)lists.boost.org >> http://lists.boost.org/mailman/listinfo.cgi/boost-users >> > >

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Some strange boost headers errors
by alfonso santimone 15 May '15

15 May '15

Hi guys, i'm a boost newbie. I've got to include boost libraries in the include path of a VisualStudio 2012 project. When i try to compile i have all these errors. Every errors is related to missing headers ( boost ones and even standard Win ones ) and to synthax errors depending on missing headers i guess. Do someone have any idea on what's wrong here? I just post here a few lines of errors, but the other ones are all of the same kind Error 1 error C2061: syntax error : identifier 'boost' C:\boost_1_57_0\boost\core\ checked_delete.hpp 24 1 csound~ Error 2 error C2059: syntax error : ';' C:\boost_1_57_0\boost\core\checked_delete.hpp 24 1 csound~ Error 3 error C2449: found '{' at file scope (missing function header?) C:\boost_1_57_0\boost\core\checked_delete.hpp 25 1 csound~ Error 4 error C2059: syntax error : '}' C:\boost_1_57_0\boost\core\checked_delete.hpp 67 1 csound~ Error 5 error C2054: expected '(' to follow 'using' C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\include\cstddef 19 1 csound~ Error 6 error C2061: syntax error : identifier 'using' C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\include\cstddef 19 1 csound~ Error 7 error C2061: syntax error : identifier 'boost' C:\boost_1_57_0\boost\smart_ptr\detail\sp_nullptr_t.hpp 23 1 csound~ Error 8 error C2059: syntax error : ';' C:\boost_1_57_0\boost\smart_ptr\detail\sp_nullptr_t.hpp 23 1 csound~ Error 9 error C2449: found '{' at file scope (missing function header?) C:\boost_1_57_0\boost\smart_ptr\detail\sp_nullptr_t.hpp 24 1 csound~ Error 10 error C2059: syntax error : '}' C:\boost_1_57_0\boost\smart_ptr\detail\sp_nullptr_t.hpp 41 1 csound~ Error 11 error C2054: expected '(' to follow 'using' C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\include\cstdlib 19 1 csound~ Error 12 error C2061: syntax error : identifier 'using' C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\include\cstdlib 19 1 csound~ Error 13 error C2061: syntax error : identifier 'abort' C:\Program Files (x86)\Microsoft Visual Studio many thanks in advance bests alfonso www.elgallorojorecords.com soundcloud.com/alfonsosantimone www.facebook.com/alfonsosantimone

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Re: [Boost-users] lexical_cast between double and string slow in Visual Studio 2013
by David Roberts 07 May '15

07 May '15

> That issue is unknown. I'd really appreciate the investigation. I have done some more investigation, and there are two factors that only cause the slowness when they both occur together. > Try excluding the lexical_cast from test, I have a feeling that this is only MSVC related issue: > > #include <sstream> > #include <string> > > int main (int, char **) > { > for (double count = 0.0; count < 1000000.0; count += 1.41) > { > std::stringstream ss; > ss << count; > std::string result = std::move(ss.str()); > ss.str(std::string()); > > ss << result; > ss >> count; > } > > return 0; > } > Running your test program does not exhibit the problem. It runs in around 3 seconds on my machine when built with either Visual Studio 2010 or Visual Studio 2013. However, changing it very slightly to match more closely what lexical_cast does internally does recreate the problem: #include <sstream> #include <string> int main (int, char **) { for (double count = 0.0; count < 1000000.0; count += 1.41) { std::stringstream ss; ss.unsetf(std::ios::skipws); ss.precision(17); ss << count; std::string result = std::move(ss.str()); ss.str(std::string()); ss << result; ss >> count; } return 0; } The effect of setting the precision to 17 is that lots of 9s appear in the string representations. (The number 17 is what boost::detail::lcast_get_precision(double*) chooses.) Without the precision call the contents of the string called result start off like this: 0 1.41 2.82 4.23 5.64 7.05 8.46 9.87 11.28 12.69 With precision set to 17 they start off like this: 0 1.4099999999999999 2.8199999999999998 4.2299999999999995 5.6399999999999997 7.0499999999999998 8.4599999999999991 9.8699999999999992 11.279999999999999 12.69 This happens for both Visual Studio 2010 and Visual Studio 2013. Then the next difference is that Visual Studio 2013 spends a lot longer handling all the extra 9s. Changing the program so that the double is converted to a string using std::stringstream without a precision call and then back to double using lexical_cast takes about 3 seconds for both Visual Studio 2010 and Visual Studio 2013. It is the combination of having all the extra 9s to parse and using Visual Studio 2013 that makes the test using lexical_cast to go both ways slow. Both Visual Studio 2010 and Visual Studio 2013 do the conversion by calling std::num_get<char,std::istreambuf_iterator<char,std::char_traits<char> > >::do_get() which then calls a function called _Stodx() which is implemented in xstod.c. This function is very different for the two versions. In Visual Studio 2010 it's a relatively thin wrapper around the C function strtod(). In Visual Studio 2013 _Stodx() has got a completely new implementation that's generated by #including xxstod.h with some macros defined. The original C function strtod() is much faster than the new _Stodx() when there are lots of 9s at the end of the strings being parsed. This modification to the program: #include <sstream> #include <string> #include <stdlib.h> int main (int, char **) { for (double count = 0.0; count < 1000000.0; count += 1.41) { std::stringstream ss; ss.unsetf(std::ios::skipws); ss.precision(17); ss << count; std::string result = std::move(ss.str()); ss.str(std::string()); ss << result; char *endptr; count = strtod(ss.str().c_str(), &endptr); } return 0; } has a runtime of about 3 seconds even though it's got to cope with all the 9s. I guess only someone from Microsoft or Dinkumware could comment on why _Stodx() was reimplemented. But the other thing is that by setting precision to 17 lexical_cast is bloating the string representations of the doubles with lots of 9s in both Visual Studio 2010 and Visual Studio 2013. Setting precision to 15 instead prevents this, and makes the original test run faster even with Visual Studio 2013 (about 4 seconds rather than 10). Regards, David

5 4

[boost.geometry] buffer distance strategies
by gchlebus 09 Mar '15

09 Mar '15

Hi, I am wondering whether it would be possible to achieve anisotropic buffering (distances in neg x, pos x, neg y, pos y can have different values) of a polygon using the buffer function with custom-implemented distance strategy. What I want to achieve is presented on the figure 2-b in the following paper: http://itcnt05.itc.nl/agile_old/Conference/mallorca2002/proceedings/posters… I would be grateful to hear from you whether it is doable, and if positive, how one could implement such a custom distance strategy. Best, -- View this message in context: http://boost.2283326.n4.nabble.com/boost-geometry-buffer-distance-strategie… Sent from the Boost - Users mailing list archive at Nabble.com.

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Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

Hi, I'm looking for a solution to serialize boost::statechart objects. I'm aware that this feature is on the statechart library todo list but was wondering if there are any workaround to achieve this with the latest boost release (1.34) ? thanks for your help ! mbrodeur65 -- View this message in context: http://www.nabble.com/Statechart-serialization-tf4131326.html#a11749139 Sent from the Boost - Users mailing list archive at Nabble.com.

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[msm] Stuck in pseudo exit
by Chrisopher Vogl 02 Mar '15

02 Mar '15

Hi all, I have got a sub state machine (called Calibrate) which is exited via a pseudo exit on an event called Ev_Exit. The event is triggered on the return of a synchronous D-Bus call. So far everything works fine. Now I wanted to use an async D-Bus call and trigger the event in the finished-handler of the asynchronous D-Bus call. I can see that the event is released and that the transition into the pseudo exit takes place but the control is not given back to the outer state machine, i.e. the following transition in the outer state machine is not executed: Row < Calibrate::exit_pt<PseudoExit> , Ev_Exit , CheckNFC , none , none >, Instead I get the log output that there is no transition for event Ev_Exit in the sub machine: user.notice tm-calibration: void hale::tmop::Calibration_::Calibrate_::CheckKconst::on_exit(const Event&, FSM&) [with Event = hale::tmop::Ev_Exit; FSM = boost::msm::back::state_machine<hale::tmop::Calibration_::Calibrate_>] user.notice tm-calibration: void hale::tmop::PseudoExit::on_entry(const Event&, FSM&) [with Event = hale::tmop::Ev_Exit; FSM = boost::msm::back::state_machine<hale::tmop::Calibration_::Calibrate_>] user.notice tm-calibration: void hale::tmop::Calibration_::Calibrate_::no_transition(const Event&, FSM&, int) [with FSM = boost::msm::back::state_machine<hale::tmop::Calibration_::Calibrate_>; Event = hale::tmop::Ev_Exit], No transition from state I get the same behaviour when I try to use Glib's signal_timeout() to generate timeout events in a sub machine. Then the sub machine gets also stuck in the pseudo exit. I'm using boost 1.53. The program is not multi-threaded and I'm using Glib's main loop. Part of transition table in sub machine called Calibrate: ... Row < CheckKconst , Ev_Exit , PseudoExit , none , is_exit_ok >, Row < CheckKconst , Ev_Exit , ShowDesc , showImpError , is_exit_error >, ... with enum ExitReason { EXIT_REASON_NONE, EXIT_REASON_OK, EXIT_REASON_TIMEOUT, EXIT_REASON_ERROR }; struct Ev_Exit { ExitReason exitReason_; std::string message_; int code_; Ev_Exit() : exitReason_( EXIT_REASON_NONE ), code_( 0 ) {} Ev_Exit( ExitReason exitReason, std::string message = "", int code = 0 ) : exitReason_( exitReason ), message_( message ), code_( code ) {} template <class Event> Ev_Exit( Event const& ) : exitReason_( EXIT_REASON_NONE ), code_( 0 ) {} }; struct is_exit_ok { template <class EVT, class FSM, class SourceState, class TargetState> bool operator()( EVT const& evt, FSM& fsm, SourceState& ss, TargetState& ts ) { return evt.exitReason_ == EXIT_REASON_OK; } }; struct PseudoExit : public msm::front::exit_pseudo_state<Ev_Exit> { template <class Event,class FSM> void on_entry( Event const& evt, FSM& fsm ) {} template <class Event,class FSM> void on_exit( Event const& evt, FSM& fsm ) {} };

2 1

problems building
by Nathan Ridge 28 Feb '15

28 Feb '15

Hi list, I'm trying to build Boost for the first time in a while, and getting unexpected errors. I have a git checkout of the 'master' branch, but I've also tried with the 'boost-1.57.0' tag and had the same problem. The build command I'm running is './b2 --with-filesystem', and the errors I'm getting are of the following form: gcc.compile.c++ bin.v2/libs/system/build/gcc-4.9.0/release/threading-multi/error_code.o In file included from libs/system/src/error_code.cpp:16:0: ./boost/system/error_code.hpp:18:39: fatal error: boost/utility/enable_if.hpp: No such file or directory #include <boost/utility/enable_if.hpp> ^ compilation terminated. "g++" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_SYSTEM_DYN_LINK=1 -DNDEBUG -I"." -c -o "bin.v2/libs/system/build/gcc-4.9.0/release/threading-multi/error_code.o" "libs/system/src/error_code.cpp" Full output is here: http://pastebin.com/fgReAxTE Looking at [1], boost/system/error_code.hpp does indeed include <boost/utility/enable_if.hpp>, and looking at [2], there is indeed no 'enable_if.hpp' in boost/utility, so I'm not sure how it's _supposed_ to work. What am I missing? Thanks, Nate [1] https://github.com/boostorg/system/blob/master/include/boost/system/error_c… [2] https://github.com/boostorg/utility/tree/master/include/boost/utility

3 5

[Units] Heterogeneous unit for pressure per time
by Dina Goldshtein 28 Feb '15

28 Feb '15

Hi, I asked about this in StackOverflow<http://stackoverflow.com/questions/27519186/boost-heterogeneous-unit-bar-pe…> but didn't get any answers so I thought I'd try here as well. I need to create a unit which represents pressure per time, specifically Bar per Minute. I tried creating it in the same way as I created similar units before: typedef boost::units::derived_dimension<boost::units::length_base_dimension, -1, boost::units::mass_base_dimension, 1, boost::units::time_base_dimension, -3>::type pressure_roc_dimension; typedef boost::units::unit<pressure_roc_dimension, boost::units::make_system<boost::units::metric::bar_base_unit, boost::units::metric::minute_base_unit>::type> bar_per_minute_unit; BOOST_UNITS_STATIC_CONSTANT(BarPerMinute, bar_per_minute_unit::unit_type); typedef boost::units::quantity<bar_per_minute_unit, double> BarPerMinuteRoC; And then I try to use it: BarPerMinuteRoC bpm = 5.0 * BarPerMinute; But this line doesn't compile with quite a long error trail which I'm having a bit of trouble understanding fully. 1>c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(197): error C2039: 'item' : is not a member of 'boost::units::dimensionless_type' 1> c:\workspace\externals\boost_1_57_0\include\boost\units\dimensionless_type.hpp(37) : see declaration of 'boost::units::dimensionless_type' 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(259) : see reference to class template instantiation 'boost::units::detail::determine_extra_equations_skip_zeros_impl<true,false>::apply<RowsBegin,1,1,3,Result>' being compiled 1> with 1> [ 1> RowsBegin=boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>,boost::units::detail::determine_extra_equations_skip_zeros_impl<false,true>::apply<boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>,1,0,3,boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>>,boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>>>::next_equations> 1> , Result=boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>>,boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>> 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(264) : see reference to class template instantiation 'boost::units::detail::determine_extra_equations<2,false>::apply<boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>,boost::units::detail::determine_extra_equations_skip_zeros_impl<false,true>::apply<boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>,1,0,3,Result>::next_equations>,3,Result>' being compiled 1> with 1> [ 1> Result=boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>>,boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>> 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(538) : see reference to class template instantiation 'boost::units::detail::determine_extra_equations<3,false>::apply<Matrix,3,Matrix>' being compiled 1> with 1> [ 1> Matrix=boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>>,boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>> 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(828) : see reference to class template instantiation 'boost::units::detail::make_square_and_invert<boost::units::list<boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<0,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::detail::make_zero_vector<0>::type>>>,boost::units::list<boost::units::list<boost::units::static_rational<-1,1>,boost::units::list<boost::units::static_rational<1,1>,boost::units::list<boost::units::static_rational<-2,1>,boost::units::detail::expand_dimensions<0>::apply<boost::units::dimensionless_type,boost::units::dimensionless_type>::type>>>,boost::units::dimensionless_type>>>' being compiled 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(1032) : see reference to class template instantiation 'boost::units::detail::normalize_units<T>' being compiled 1> with 1> [ 1> T=boost::units::list<boost::units::scaled_base_unit<boost::units::si::second_base_unit,boost::units::scale<60,boost::units::static_rational<1,1>>>,boost::units::list<boost::units::metric::bar_base_unit,boost::units::dimensionless_type>> 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\detail\linear_algebra.hpp(1051) : see reference to class template instantiation 'boost::units::detail::calculate_base_unit_exponents_impl<false>::apply<T,Dimensions>' being compiled 1> with 1> [ 1> T=boost::units::list<boost::units::scaled_base_unit<boost::units::si::second_base_unit,boost::units::scale<60,boost::units::static_rational<1,1>>>,boost::units::list<boost::units::metric::bar_base_unit,boost::units::dimensionless_type>> 1> , Dimensions=BSII::Units::pressure_roc_dimension 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\heterogeneous_system.hpp(243) : see reference to class template instantiation 'boost::units::detail::calculate_base_unit_exponents<boost::units::list<boost::units::scaled_base_unit<boost::units::si::second_base_unit,boost::units::scale<60,boost::units::static_rational<1,1>>>,boost::units::list<T,boost::units::dimensionless_type>>,Dimensions>' being compiled 1> with 1> [ 1> T=boost::units::metric::bar_base_unit 1> , Dimensions=BSII::Units::pressure_roc_dimension 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\unit.hpp(92) : see reference to class template instantiation 'boost::units::detail::make_heterogeneous_system<Dim,System>' being compiled 1> with 1> [ 1> Dim=BSII::Units::pressure_roc_dimension 1> , System=boost::units::homogeneous_system<boost::units::list<boost::units::scaled_base_unit<boost::units::si::second_base_unit,boost::units::scale<60,boost::units::static_rational<1,1>>>,boost::units::list<boost::units::metric::bar_base_unit,boost::units::dimensionless_type>>> 1> ] 1> c:\workspace\externals\boost_1_57_0\include\boost\units\unit.hpp(99) : see reference to class template instantiation 'boost::units::reduce_unit<S1>' being compiled 1> with 1> [ 1> S1=BSII::Units::bar_per_minute_unit 1> ] 1> c:\workspace\foundations\sw_foundations\bsii_common\test\src\units\units_pressure_test.cpp(97) : see reference to class template instantiation 'boost::units::is_implicitly_convertible<BSII::Units::bar_per_minute_unit,Unit>' being compiled 1> with 1> [ 1> Unit=BSII::Units::bar_per_minute_unit 1> ] According to the Boost documentation a homogeneous system can only be composed of linearly independent base units. In my case, I'm trying to mix bars (which in turn "contain" seconds as the time element) with minutes. This sounds problematic to me. But on the other hand, since I don't include mass and length base units in my system it seems to me that the base is independent after all. In any case, I searched online for an example of creating such a heterogeneous unit but didn't find anything comprehensible. Also, I read in the Boost documentation that a heterogeneous unit doesn't preserve information about how it was created. Does this mean I won't be able to, for instance, multiply BarPerMinuteRoC by Minute and get Bar back? Thanks a lot! Dina This message (including any attachments) is intended only for the use of the individual or entity to which it is addressed and may contain materials protected by copyright or information that is non-public, proprietary, privileged, confidential, and exempt from disclosure under applicable law or agreement. If you are not the intended recipient, you are hereby notified that any review use, dissemination, distribution, or duplication of this communication is strictly prohibited. If you are not the intended recipient, please contact the sender immediately by reply email and destroy all copies of the original. Thank you.

2 2

[Preprocessor] Compile error after change from Boost 1.55 to 1.57
by Franz Alt 27 Feb '15

27 Feb '15

Hi, I've written some preprocessor directives to generate functions for a class. With Boost 1.55 everything works fine with gcc and clang. When I try to change to Boost 1.57 I've got some strange compile errors. I'm happy if someone could help. Thanks Franz gcc 4.9.1 failed with error: test.cpp:33:1: error: macro "BOOST_PP_SEQ_ELEM_III" requires 2 arguments, but only 1 given ) ^ test.cpp:33:1: error: macro "BOOST_PP_VARIADIC_ELEM_2" requires 4 arguments, but only 2 given test.cpp:60:1: error: macro "BOOST_PP_SEQ_ELEM_III" requires 2 arguments, but only 1 given MY_FUNCTION_BEGIN((b)) ^ test.cpp:60:1: error: macro "BOOST_PP_VARIADIC_ELEM_2" requires 4 arguments, but only 2 give clang 3.5.0 failed with error: test.cpp:30:3: error: too few arguments provided to function-like macro invocation MY_FUNCTIONS( \ ^ test.cpp:25:25: note: expanded from macro 'MY_FUNCTIONS' BOOST_PP_SEQ_FOR_EACH(FUNCTION_DECL, _, seq) ^ ..../boost.1_57_0/boost/preprocessor/seq/for_each.hpp:26:67: note: expanded from macro 'BOOST_PP_SEQ_FOR_EACH' # define BOOST_PP_SEQ_FOR_EACH(macro, data, seq) BOOST_PP_FOR((macro, data, seq (nil)), BOOST_PP_SEQ_FOR_EACH_P, BOOST_PP_SEQ_FOR_EACH_O, BOOST_PP_SEQ_FOR_EACH_M) ^ ..../boost.1_57_0/boost/preprocessor/repetition/detail/for.hpp:22:78: note: expanded from macro 'BOOST_PP_FOR_1' # define BOOST_PP_FOR_1(s, p, o, m) BOOST_PP_FOR_1_C(BOOST_PP_BOOL(p(2, s)), s, p, o, m) ^ note: (skipping 18 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all) packages/boost/boost_i4/boost/preprocessor/seq/elem.hpp:22:39: note: expanded from macro 'BOOST_PP_SEQ_ELEM' # define BOOST_PP_SEQ_ELEM(i, seq) BOOST_PP_SEQ_ELEM_I(i, seq) ^ packages/boost/boost_i4/boost/preprocessor/seq/elem.hpp:41:45: note: expanded from macro 'BOOST_PP_SEQ_ELEM_I' # define BOOST_PP_SEQ_ELEM_I(i, seq) BOOST_PP_SEQ_ELEM_II(BOOST_PP_SEQ_ELEM_ ## i seq) ^ packages/boost/boost_i4/boost/preprocessor/seq/elem.hpp:43:62: note: expanded from macro 'BOOST_PP_SEQ_ELEM_II' # define BOOST_PP_SEQ_ELEM_II(im) BOOST_PP_SEQ_ELEM_III(im) ^ packages/boost/boost_i4/boost/preprocessor/seq/elem.hpp:44:13: note: macro 'BOOST_PP_SEQ_ELEM_III' defined here # define BOOST_PP_SEQ_ELEM_III(x, _) x The program is: #include <iostream> #ifndef BOOST_PP_VARIADICS #define BOOST_PP_VARIADICS #endif #include <boost/preprocessor.hpp> #define ADD_CONST_REF(op, data, elem) elem const & #define FUNCTION_DECL(r, data, tup) \ double BOOST_PP_TUPLE_ELEM(0, tup) \ BOOST_PP_IF(BOOST_PP_LIST_IS_NIL(BOOST_PP_TUPLE_TO_LIST(BOOST_PP_TUPLE_ELEM(1, tup))), \ (), \ BOOST_PP_SEQ_TO_TUPLE( \ BOOST_PP_SEQ_TRANSFORM( \ ADD_CONST_REF, \ _, \ BOOST_PP_TUPLE_TO_SEQ(BOOST_PP_LIST_TO_TUPLE(BOOST_PP_TUPLE_TO_LIST(BOOST_PP_TUPLE_ELEM(1, tup)))) \ ) \ ) \ ) \ const; #define MY_FUNCTIONS(seq) \ BOOST_PP_SEQ_FOR_EACH(FUNCTION_DECL, _, seq) class Foo { public: MY_FUNCTIONS( \ ((a, (int))) \ ((b) ) \ ) }; #define ADD_ARG(op, data, elem) elem const & BOOST_PP_CAT(a_, elem) #define MY_FUNCTION_BEGIN(tup) \ double Foo::BOOST_PP_TUPLE_ELEM(0, tup) \ BOOST_PP_IF(BOOST_PP_LIST_IS_NIL(BOOST_PP_TUPLE_TO_LIST(BOOST_PP_TUPLE_ELEM(1, tup))), \ (), \ BOOST_PP_SEQ_TO_TUPLE( \ BOOST_PP_SEQ_TRANSFORM( \ ADD_ARG, \ _, \ BOOST_PP_TUPLE_TO_SEQ(BOOST_PP_LIST_TO_TUPLE(BOOST_PP_TUPLE_TO_LIST(BOOST_PP_TUPLE_ELEM(1, tup)))) \ ) \ ) \ ) const \ { #define MY_FUNCTION_END() } MY_FUNCTION_BEGIN((a, (int))) { std::cout << "Foo::a(" << a_int << ")\n"; } MY_FUNCTION_END() MY_FUNCTION_BEGIN((b)) { std::cout << "Foo::b()\n"; } MY_FUNCTION_END() int main() { Foo f; f.a(42); f.b(); return 0; }

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VMD library accepted
by Steven Watanabe 27 Feb '15

27 Feb '15

AMDG The VMD library submitted by Edward Diener is ACCEPTED into Boost. I apologize for the long delay for this announcement. Thanks to everyone who participated in the formal review * Nial Douglass * Bjorn Reese * Rodrigo Madera * Zhou Zhenghui * Matt Calabrese * Paul Mensonides Reviews for the library were generally positive. The library was considered to be a useful set of tools for macro programmers. Paul expressed concern about the way the the library handles v-sequences and v-identifiers. After some discussion, Edward has agreed that the interface could be significantly improved. Work Items: * Add examples and improved motivation in the documentation * Update the v-identifier/v-sequence interface based on Paul's comments * Fix inaccurate statements about Boost.Preprocessor per Paul In Christ, Steven Watanabe

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[Regex] Cannot build Regex without ICU
by Rob Desbois 26 Feb '15

26 Feb '15

I want to build the Boost libs without ICU support in Regex, but have been unable to prevent it from being linked in. I've run the following commands on a freshly extracted distribution of 1.57: ./bootstrap.sh --without-icu --prefix=/home/rob/workspace/deps/boost/1.57.0/linux/x64/ ./b2 install The bootstrap stage output includes this, which seems to indicate it's behaving correctly: Unicode/ICU support for Boost.Regex?... disabled. The resulting project-config.jam makes no mention of ICU. The build log includes: - has_icu builds : yes - icu : yes The shared library dependencies for the resulting libboost_regex.so.1.57.0 then include: libicuuc.so.50 => /lib64/libicuuc.so.50 (0x00007f74e5e3b000) libicui18n.so.50 => /lib64/libicui18n.so.50 (0x00007f74e5a3b000) libicudata.so.50 => /lib64/libicudata.so.50 (0x00007f74e4467000) I know the docs for Boost.Regex specify the bootstrap argument as --disable-icu, however this is rejected as invalid, unlike the argument I provide. Have I messed up somewhere or is this a bug? TIA -- rob -- Rob Desbois http://theotherbranch.wordpress.com/

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Re: [Boost-users] [ASIO] io_service::service::shutdown_service
by chmhou＠sina.com 25 Feb '15

25 Feb '15

>Hi, >Let us consider following execution sequence: >1. "io_service" destructor calls "io_service::service::shutdown_service"; >2. documentation of "io_service::service::shutdown_service" says that it >should destroy all user defined handler objects. >Is it true that user defined handler objects may access to (e.g. post a >handler) that "io_service" being destroyed and therefore has not exist >already? >Could You please also clarify me what does "user defined handler object" >really mean? >Thanks, >Andrew. Hi, Andrew For your 2nd question "user defined handler object", I supposed that the parameter for the io_service::post() which is kinda "user defined handler object". 1st, it could be a handler like "bind(&fun, this, _1, _2)". Martin

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Why does read_xml call fail if my property tree contains char16_t?
by ashish g 24 Feb '15

24 Feb '15

Hi I have a property tree which has strings of char16_t as both key and value datatypes. When I try to call read_xml() to load an xml file into this tree it fails. The same code however works with wchar_t. Seems like its failing on parse_bom() function. The code and error message can be seen here: http://coliru.stacked-crooked.com/a/3f922b43838fd7e8 Any tips on how to fix this issue. -- *Ashish Gudla*

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[fusion] Why is the std::tuple adapter undocumented?
by Rob Desbois 24 Feb '15

24 Feb '15

What it says on the tin really: Why is boost/fusion/adapted/std_tuple.hpp not documented at all? I'd like to use it but if it's undocumented because it's considered experimental then I'll use fusion's vector instead... TIA -- rob -- Rob Desbois http://theotherbranch.wordpress.com/

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Re: [Boost-users] Performance optimization in Boost using std::vector<>
by chmhou＠sina.com 24 Feb '15

24 Feb '15

Hi I got it, it supposed that I made a mistake on the duration. I will follow this question. Martin

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Re: [Boost-users] Performance optimization in Boost using std::vector<>
by chmhou＠sina.com 23 Feb '15

23 Feb '15

>Hi, >not sure if the OP needs std::vector but... I'd recommend >boost::container::vector which has a dedicated constructor [1] and >resize() [2] method tagged with default_init_t argument, both of which >default initialize the values in the vector. For primitives it basically >means it leaves them uninitialized, hence there's no overhead when the >vector is to be filled with real data soon. >WBR, >Adam Romanek Hi Adam As following your point, the benefit of boost::container::vector supported the "default_init_t" method so that it 's quite convince and safety comparing with std::vector<> is that right ? are there additional advantages ? Hi Ilja You said "Boost::mpi version is always at least 10 times slower. " make me confused, I guess it's should be a typo, isn't ? Martin

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Signals2 benchmark
by Joren Heit 22 Feb '15

22 Feb '15

Hi all, New to this list, so I hope I'm at the right place, and not asking too much of you guys. Please inform me if either of those is true! ;-) I have been working on a little toy project to implement a template-based Signal/Slot library and now that I have a usable end-product, I want to test it against boost::signals2 to get an idea of how well it performs. Therefore my first question is whether boost::signals2 is generally considered a high performance library. Second, I'm a little reluctant to build a benchmark suite myself, because I want to be fair to both myself and the other party. I don't know the signals2 library at all, let alone what its virtues and shortcomings are. Some tips on what to test exactly would therefore be great, although I'm afraid this request might qualify for "asking too much". Initial tests show that my own library can be up to 10 times faster than the boost-implementation, which makes me even more suspicious that I might not be testing the right things (but at the same time prematurely proud). Thanks in advance and cheers! Joren

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[ASIO] io_service::service::shutdown_service
by Andrew C 22 Feb '15

22 Feb '15

Hi, Let us consider following execution sequence: 1. "io_service" destructor calls "io_service::service::shutdown_service"; 2. documentation of "io_service::service::shutdown_service" says that it should destroy all user defined handler objects. Is it true that user defined handler objects may access to (e.g. post a handler) that "io_service" being destroyed and therefore has not exist already? Could You please also clarify me what does "user defined handler object" really mean? Thanks, Andrew.

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Re: [Boost-users] Strange boost::threads behaviour
by Gavin Lambert 20 Feb '15

20 Feb '15

On 19/02/2015 21:11, Lorenzo Trivelli wrote: >> >> Typically the way things work is that as long as a lock (or >> whatever it is you're using -- you didn't actually say) goes >> uncontended, or minimally contended such that a spin resolves it, >> then it will allocate no kernel handles. A kernel handle is only >> required when the lock is contended for sufficiently long that it >> needs to put the thread to sleep. > > thank you ver much for your response, > I'll try to detail the issue better. > The original software is an conccurrent transactional server which > preallocates a certain number of ftherads (say 100 ~ 130) and then > accepts and serves TCP/IP connections in a request-reply fashion. While thread-per-connection is a popular model for older or small-scale software (because it's easy to program), performance suffers quite significantly when a large number of connections are in use, especially when each connection needs to contend on the same locks. Especially if the workload is mostly I/O bound rather than CPU bound, you may want to consider a "properly" async design (eg. using Boost.Asio) where #threads == #cores (or thereabouts) and connection processing can shift between threads as needed. > Obviuosly, it heavily uses boost::shared_ptr to handle these connections, > but in the end I managed to use other shared pointers (for testing purposes only) > and the boost::thread object alone and a single shared static mutex object > > so, the sample program starrts, creates some threads which simply does some memory > allocations loops and s. In the main function I enclosed all the code between brackets, > and I print the handle count before and after, ans it's not the same, > something like > int main() { > GetProcessHandleCount().... > > { > [creates threads and waits for their termination through ->join] > > } > GetProcessHandleCount().... > > } > > The difference between the first and the last count is not always the same, it > depends on how much concccurent threads you create and how much iterations of the > same loop each thread does. Well, as I said that is not an error if some synchronization objects (eg. mutexes) still exist.

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"xtime" ambiguous symbol in MSVC 12
by Kevin Williams 19 Feb '15

19 Feb '15

Hi I get a C2872 when including "chrono" (allegedly line 738) from MSVC 12, and also needing boost::mutex. I believe the boost mutex is a bit faster than std::mutex, and I need that. Many thanks, Kevin

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Re: [Boost-users] Strange boost::threads behaviour
by Gavin Lambert 19 Feb '15

19 Feb '15

On 17/02/2015 04:01, Lorenzo Trivelli wrote: > While analyzing a resource exaustion problem on a production machine, > (Windows) I found out astrange behaviour of boost::threads regarding event object. > The problem is that after a certain number of iterations it semms that the > thread lib allocates an EventHandle which is never freed. > I managed to reproduce in some ways the behaviour, but I'm a bit clueless > about its reason. Typically the way things work is that as long as a lock (or whatever it is you're using -- you didn't actually say) goes uncontended, or minimally contended such that a spin resolves it, then it will allocate no kernel handles. A kernel handle is only required when the lock is contended for sufficiently long that it needs to put the thread to sleep. This handle should be released when the lock itself is deleted. If the lock is itself global or otherwise held by a global object, or if it's in an object that you are memory-leaking, then it won't go away until you close the process. > 3) if you want I can attach the sample code with a but if info > on how to reproduce the behaviour Without knowing at least *which* threading object you're using, I doubt a report will get anywhere.

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Need help to build ( cross compile) Boost for ARM
by som jagadeeshan 18 Feb '15

18 Feb '15

Hello All, Currently I’m trying to get the boost_1_57_0 library built for ARM. But i don’t find any help on how to go about this. I'm using the poky hard float tool chain to get the library cross compiled(*arm-poky-linux-gnueabi-*) Any help on how to get this will be great. The below log is what i get when running the script file ( bootstrap.sh) $ ./bootstrap.sh *Building Boost.Build engine with toolset gcc... Failed to build Boost.Build build engineConsult 'bootstrap.log' for more details* Thanks, Mike

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