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1.36.0 boost/random/uniform_01 Infinite[?] Loop
by Dave Steenburgh 17 Oct '08

17 Oct '08

I'm sure everyone will think I'm crazy, but here goes... Background: I came across this problem while developing a proof of concept for my master's project. It entails generating random numbers according to either a uniform or a normal distribution. I wrote a few wrapper classes to simplify dealing with the generators and distributions. Those wrapper classes let me do this: randomGenerator *rg; if(uniformDistribution) rg = new uniformGenerator(); else rg = new normalGenerator(); (I also have constructors that take arguments to alter the range of values, but I'm not using them presently.) Then I can retrieve values like so: (*rg)() uniformGenerator and normalGenerator inherit from randomGenerator, and are wrappers for these: boost::variate_generator<boost::minstd_rand&, boost::uniform_real<> > boost::variate_generator<boost::minstd_rand&, boost::normal_distribution<> > I currently have two programs that use those wrapper classes. One is fairly minimal; it simply parses some command line arguments that affect the distribution and quantity, then retrieves the values and prints them to stdout. The other program is my proof of concept; it does the same argument parsing (with a few more options), then makes use of the values to run my simulation, which is mostly manipulating STL containers. Problem: Now we come to the crazy part. I work mostly on one of two Windows machines, using g++ under Cygwin. On either machine, both of those programs run to completion every time, if I compile with -O1, -O2, or -O3. However, if I use -O0 (or just no -O argument), then the simulation locks up. The other program---that just prints random numbers---never locks up. (Incidentally, this program was my attempt to create a minimal program that replicated the behavior.) By single-stepping with gdb, I determined that it gets stuck in boost/random/uniform_01.hpp: 58 for (;;) { 59 result_type result = result_type(_rng() - (_rng.min)()) * _factor; 60 if (result < result_type(1)) 61 return result; 62 } gdb shows that result is always equal to 1, which of course leads to an infinite loop. Single-stepping through all of the code directly related to the random generators shows the same sequence of instructions for both programs. If I use the uniform distribution, it gets stuck when I try to retrieve the second value. If I use the normal distribution, it gets stuck on the third retrieval. Also worth noting, by default the generators are supplied with a different seed value every time I run either program. Getting back to the programming environment, when I build on the Solaris machines in my school's CS department, the program never gets stuck. For my part, it's exactly the same source, and I still use g++. I have not been able to coerce any warnings or errors from the compiler. So, I'm all out of ideas. I'm open to suggestions for fixing this, but I'm hoping the solution is less extreme than compiling gcc from source.

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Problem in compiling simple boost mpl program
by Missing Rainbow 16 Oct '08

16 Oct '08

Hi All, I am making use of boost 1.32.0 (as given in the MPL book CD). I have written a small program using mpl::vector. I am getting the following error. What could be the problem? (begin-quote) lotus 241 $ CC -I$BOOST_ROOT -c hello.c "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/if.hpp", line 63: Warning (Anachronism): Type names qualified by template parameters require "typename". "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/if.hpp", line 72: Where: While specializing "boost::mpl::if_<boost::mpl::T1, boost::mpl::T2, boost::mpl::T3>". "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/if.hpp", line 72: Where: Specialized in non-template code. "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/aux_/preprocessed/no_ttp/plus.hpp", line 148: Warning (Anachronism): Type names qualified by template parameters require "typename". "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/aux_/preprocessed/no_ttp/minus.hpp", line 148: Warning (Anachronism): Type names qualified by template parameters require "typename". "/backup/dev_area/anna/mplbookcd/boost_1_32_0/boost/mpl/vector/aux_/iterator.hpp", line 92: Error: Partial specialization parameter m_ is not used in the arguments. "hello.c", line 4: Error: mpl is not defined. "hello.c", line 4: Warning (Anachronism): Using vector as a template without a declaration. "hello.c", line 4: Error: vector is not defined. 3 Error(s) and 4 Warning(s) detected. lotus 242 $ cat hello.c #include "boost/mpl/vector.hpp" typedef mpl::vector<int, char*, double& > seq; lotus 243 $ CC -V CC: Sun C++ 5.5 2003/03/12 lotus 244 $ uname -a SunOS lotus 5.10 Generic_125100-09 sun4v sparc SUNW,Sun-Fire-T200 lotus 245 $ (end-quote) Rgds, anna

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MPL: Lazy Evaluation and Nullary Metafunction
by Missing Rainbow 16 Oct '08

16 Oct '08

Hi All, I am reading about the lazy evaluation and nullary metafunction in the MPL book. While discussing the lazy evaluation technique the following code is presented (page 57): struct add_pointer_f { template <class T> struct apply : boost::add_pointer<T> {}; }; typedef mpl::vector<int, char*, double&> seq; typedef mpl::transform<seq, boost::add_pointer<_> > calc_ptr_seq; The point of the above code was to demonstrate that the nullary metafunction calc_ptr_seq represents the sequence "int*, char**, double&*", even though the last element in that sequence is not valid. Thanks to lazy evaluation. As long as we don't access the third element in the sequence represented by calc_ptr_seq, everything should work fine. Is my understanding correct? Also, other than nullary metafunction, is there any other approach to lazy evaluation? Or will lazy evaluation _always_ be implemented with the help of nullary metafunction? Thank you. Rgds, anna

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help downloading Version 1.31.0
by Vishakh Paul Thomas 16 Oct '08

16 Oct '08

Hi I'd like to download boost Version 1.31.0 as that's what my app used earlier. We are porting the app to Linux from solaris and I do not want to try using the latest one as I am unaware of the dependencies. I looked around on boost.org and was unable to find any link to download it. Can you please let me know where I can find it? Thanks! Vishakh

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boost.program_options - reloading configuration file
by Aljaz 16 Oct '08

16 Oct '08

Hello I want to implement function in my application which would allow me to reload the configuration file. At the moment I have all neccessary program_options objects inside a configuration class, and when I do: bool configuration::reload_config_file(std::string filename) { try { std::ifstream ifs(filename.c_str()); if (!ifs.is_open()) return false; boost::program_options::store(boost::program_options::parse_config_file(ifs, m_config), m_variables); boost::program_options::notify(m_variables); ifs.close(); } catch (std::exception &e) { return false; } return true; } The options will stay the same although the configuration file is different. Should I somehow clear the m_variables object? Many thanks in advance!

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[1.35] LINK problems since I switch to wpath
by Germain BARRET 16 Oct '08

16 Oct '08

Hi, I'm still using Boost 1.35 on VC++ 2005 I had a code very well building and linking, only I had some charset problems at display. That's why I decided to switch my code to UNICODE (or like) switching all the std::string -> std::wstring In the area of boost, I also switched all the boost::filesystem::path -> boost::filesystem::wpath that was a long job, many particular cases were found for example, problemes with : boost::filesystem::exists boost::filesystem::current_path boost::filesystem::initial_path That I commented to compile. Here comes my main question !!!! Now I have some LINK problems. The librairy very well worked before, but no more now. See the error logs at the end. According to the linking log, here are the names of the libs I use (as you can see, that are STATIC Multi thread libs and that is what I want) : libboost_filesystem-vc80-mt-sgd-1_35.lib libboost_system-vc80-mt-sgd-1_35.lib libboost_thread-vc80-mt-sgd-1_35.lib libboost_date_time-vc80-mt-sgd-1_35.lib The link problems are on : boost::filesystem::detail::status_api boost::filesystem::detail::dir_itr_increment boost::filesystem::detail::dir_itr_first Error logs : Error 2 error LNK2019: unresolved external symbol "class boost::filesystem::file_status __cdecl boost::filesystem::detail::status_api(class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > const &,class boost::system::error_code &)" (?status_api@detail @filesystem@boost@@YA?AVfile_status@23@ABV?$basic_string@GU?$char_traits@G @std@@V?$allocator@G@2@@std@@AAVerror_code@system@3@@Z) referenced in function "bool __cdecl boost::filesystem::is_regular<class boost::filesystem::basic_path<class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> >,struct boost::filesystem::wpath_traits> >(class boost::filesystem::basic_path<class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> >,struct boost::filesystem::wpath_traits> const &)" (??$is_regular@V ?$basic_path@V?$basic_string@GU?$char_traits@G@std@@V?$allocator@G@2@@std@ @Uwpath_traits@filesystem@boost@@@filesystem@boost@@@filesystem@boost @@YA_NABV?$basic_path@V?$basic_string@GU?$char_traits@G@std@@V?$allocator@G @2@@std@@Uwpath_traits@filesystem@boost@@@01@@Z) DirectoryInfoManager.obj Error 3 error LNK2001: unresolved external symbol "class boost::filesystem::file_status __cdecl boost::filesystem::detail::status_api(class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > const &,class boost::system::error_code &)" (?status_api@detail @filesystem@boost@@YA?AVfile_status@23@ABV?$basic_string@GU?$char_traits@G @std@@V?$allocator@G@2@@std@@AAVerror_code@system@3@@Z) Patch.obj Error 4 error LNK2019: unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::dir_itr_increment(void * &,class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > &,class boost::filesystem::file_status &,class boost::filesystem::file_status &)" (?dir_itr_increment@detail@filesystem@boost@@YA?AVerror_code@system @3@AAPAXAAV?$basic_string@GU?$char_traits@G@std@@V?$allocator@G@2@@std@ @AAVfile_status@23@2@Z) referenced in function "private: void __thiscall boost::filesystem::basic_directory_iterator<class boost::filesystem::basic_path<class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> >,struct boost::filesystem::wpath_traits> >::increment(void)" (?increment@ ?$basic_directory_iterator@V?$basic_path@V?$basic_string@GU?$char_traits@G @std@@V?$allocator@G@2@@std@@Uwpath_traits@filesystem@boost@ @@filesystem@boost@@@filesystem@boost@@AAEXXZ) Patch.obj Error 5 error LNK2019: unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::dir_itr_first(void * &,class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > const &,class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > &,class boost::filesystem::file_status &,class boost::filesystem::file_status &)" (?dir_itr_first@detail@filesystem@boost@@YA?AVerror_code@system@3@AAPAXABV ?$basic_string@GU?$char_traits@G@std@@V?$allocator@G@2@@std@ @AAV67@AAVfile_status@23@3@Z) referenced in function "private: class boost::system::error_code __thiscall boost::filesystem::basic_directory_iterator<class boost::filesystem::basic_path<class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> >,struct boost::filesystem::wpath_traits> >::m_init(class boost::filesystem::basic_path<class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> >,struct boost::filesystem::wpath_traits> const &)" (?m_init@ ?$basic_directory_iterator@V?$basic_path@V?$basic_string@GU?$char_traits@G @std@@V?$allocator@G@2@@std@@Uwpath_traits@filesystem@boost@ @@filesystem@boost@@@filesystem@boost@@AAE?AVerror_code@system@3@ABV ?$basic_path@V?$basic_string@GU?$char_traits@G@std@@V?$allocator@G@2@@std@ @Uwpath_traits@filesystem@boost@@@23@@Z) Patch.obj

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asio and usb ports?
by Graham Reitz 16 Oct '08

16 Oct '08

Is the asio::serial_port library able to work with usb ports/devices? Thanks, graham

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Re: [Boost-users] Error:" Non-const function called for const object" on Sun CC while using boost::multi_index::multi_index_container
by Alexander Vinokur 16 Oct '08

16 Oct '08

Done. Now it works fine. % CC -m64 -library=stlport4 -I./boost_patch -I/home/BOOST/boost_1_34_0 foo1.cpp // No problem Thanks, Alex Vinokur "JOAQUIN M. LOPEZ MU?OZ" <joaquin(a)tid.es> wrote in message news:<D1B8B06869125E44A4B33FF31CBAEA591187ADF181(a)EXCLU2K7.hi.inet>... ________________________________________ De: Alexander Vinokur [Alexander.Vinokur(a)amdocs.com] Enviado el: domingo, 12 de octubre de 2008 8:44 Para: boost-users(a)lists.boost.org CC: JOAQUIN M. LOPEZ MU?OZ Asunto: Re: Error:" Non-const function called for const object" on Sun CC = while using boost::multi_index::multi_index_container > > Hi Joaqu?n, > > I was out of office several days. Sorry. > So, I send my reply today. No problem at all :) > I don't have permissions to change something under /boost. Maybe you can still perform the test by doing the following: 1 Create a local folder structure more or less like this: ~alex/boost_patch/boost/detail and copy there the allocator_utilities.hpp modified file I sent you previ=usly. 2 When compiling your multi-index example add a compiler option (or IDE setting, etc.) so that ~alex/boost_patch/ is added to the list of include directories *and* takes precedence over the official copy of Boos=. If you finally manage to do the test please report back your results. > But here other test I did: [example core snipped] I take this a sufficient evidence that the patch should work, so I went ahe=d and added it to the trunk: http://svn.boost.org/trac/boost/changeset/49289 If nothing wrong happens with the patch, it'll be shipped with Boost 1.38. Joaqu?n M L?pez Mu?oz Telef?nica, Investigaci?n y Desarrollo ---------- This message and the information contained herein is proprietary and confidential and subject to the Amdocs policy statement, you may review at http://www.amdocs.com/email_disclaimer.asp

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Iostreams tag dispatch failure?
by Stéphane Perras 16 Oct '08

16 Oct '08

Hi all, I've been trying to compile the container_source example from the boost/iostreams documentation for a couple of days actually without success. It seems to me that tag dispatching fails to dispatch the default (for any_tag) implementation for optimal_buffer_size( ), imbue( ) and flush( ). I'm using Visual C++ 2005 SP1. I saw one unanswered posting about this exact problem early 2007, but on GCC. So I guess from this that I'm missing something obvious. Thanks for any help. Steph. Ps: code and build log following. #include "stdafx.h" #include <algorithm> // copy, min #include <iosfwd> // streamsize #include <boost/iostreams/categories.hpp> // source_tag #include <boost/iostreams/stream.hpp> #include <string> template<typename Container> class container_source; template<typename Container> class container_source { public: typedef typename Container::value_type char_type; typedef boost::iostreams::source_tag category; container_source(Container& container) : container_(container), pos_(0) { } std::streamsize read(char_type* s, std::streamsize n) { using namespace std; streamsize amt = static_cast<streamsize>(container_.size() - pos_); streamsize result = (min)(n, amt); if (result != 0) { std::copy( container_.begin() + pos_, container_.begin() + pos_ + result, s ); pos_ += result; return result; } else { return -1; // EOF } } Container& container() { return container_; } private: typedef typename Container::size_type size_type; Container& container_; size_type pos_; }; int main(int argc, char* argv[]) { using namespace std; typedef container_source<string> string_source; string input = "Hello World!\nThis is a test...\nShouldn't break\nthe assert"; string output; boost::iostreams::stream<string_source> in(input); getline(in, output); assert(input == output); return 0; } Build log: ------ Build started: Project: tstIostreams, Configuration: Debug Win32 ------ Compiling... tstIostreams.cpp e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\optimal_buffer_size.hpp(39) : error C2039: 'optimal_buffer_size' : is not a member of 'boost::iostreams::detail::optimal_buffer_size_impl<T>' with [ T=string_source ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(162) : see reference to function template instantiation 'std::streamsize boost::iostreams::optimal_buffer_size<T>(const T &)' being compiled with [ T=string_source ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(155) : while compiling class template member function 'void boost::iostreams::detail::indirect_streambuf<T,Tr,Alloc,Mode>::open(const T &,int,int)' with [ T=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char>, Mode=boost::iostreams::detail::io_mode_impl<1>::type ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(195) : while compiling class template member function 'bool boost::iostreams::detail::indirect_streambuf<T,Tr,Alloc,Mode>::is_open(void) const' with [ T=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char>, Mode=boost::iostreams::detail::io_mode_impl<1>::type ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\stream_buffer.hpp(65) : see reference to class template instantiation 'boost::iostreams::detail::indirect_streambuf<T,Tr,Alloc,Mode>' being compiled with [ T=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char>, Mode=boost::iostreams::detail::io_mode_impl<1>::type ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\utility\base_from_member.hpp(69) : see reference to class template instantiation 'boost::iostreams::stream_buffer<T,Tr,Alloc>' being compiled with [ T=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\stream.hpp(75) : see reference to class template instantiation 'boost::base_from_member<MemberType>' being compiled with [ MemberType=boost::iostreams::stream_buffer<string_source,std::char_traits<char>,std::allocator<char>> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\stream.hpp(112) : see reference to class template instantiation 'boost::iostreams::detail::stream_base<Device,Tr,Alloc>' being compiled with [ Device=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char> ] e:\data\tstcsharp\tstiostreams\tstiostreams\tstiostreams.cpp(52) : see reference to class template instantiation 'boost::iostreams::stream<Device>' being compiled with [ Device=string_source ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\imbue.hpp(38) : error C2039: 'imbue' : is not a member of 'boost::iostreams::detail::imbue_impl<T>' with [ T=container_source<std::string> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\adapter\concept_adapter.hpp(113) : see reference to function template instantiation 'void boost::iostreams::imbue<container_source<Container>,Locale>(T &,const Locale &)' being compiled with [ Container=std::string, Locale=std::locale, T=container_source<std::string> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(225) : see reference to function template instantiation 'void boost::iostreams::detail::concept_adapter<T>::imbue<std::locale>(const Locale &)' being compiled with [ T=string_source, Locale=std::locale ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(223) : while compiling class template member function 'void boost::iostreams::detail::indirect_streambuf<T,Tr,Alloc,Mode>::imbue(const std::locale &)' with [ T=string_source, Tr=std::char_traits<char>, Alloc=std::allocator<char>, Mode=boost::iostreams::detail::io_mode_impl<1>::type ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\flush.hpp(41) : error C2039: 'flush' : is not a member of 'boost::iostreams::detail::flush_device_impl<T>' with [ T=container_source<std::string> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\adapter\concept_adapter.hpp(157) : see reference to function template instantiation 'bool boost::iostreams::flush<Device>(T &)' being compiled with [ Device=container_source<std::string>, T=container_source<std::string> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\adapter\concept_adapter.hpp(106) : see reference to function template instantiation 'bool boost::iostreams::detail::device_wrapper_impl<boost::iostreams::any_tag>::flush<container_source<Container>,std::basic_streambuf<_Elem,_Traits>>(Device &,Dummy *)' being compiled with [ Container=std::string, _Elem=char, _Traits=std::char_traits<char>, Device=container_source<std::string>, Dummy=std::basic_streambuf<char,std::char_traits<char>> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\adapter\concept_adapter.hpp(105) : while compiling class template member function 'bool boost::iostreams::detail::concept_adapter<T>::flush(std::basic_streambuf<_Elem,_Traits> *)' with [ T=string_source, _Elem=char, _Traits=std::char_traits<char> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\optional.hpp(35) : see reference to class template instantiation 'boost::iostreams::detail::concept_adapter<T>' being compiled with [ T=string_source ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\optional.hpp(38) : see reference to class template instantiation 'boost::iostreams::detail::aligned_storage<T>::dummy_u' being compiled with [ T=boost::iostreams::detail::concept_adapter<string_source> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\optional.hpp(108) : see reference to class template instantiation 'boost::iostreams::detail::aligned_storage<T>' being compiled with [ T=boost::iostreams::detail::concept_adapter<string_source> ] e:\data\tstcsharp\boost_1_36_0\include\boost-1_36\boost\iostreams\detail\streambuf\indirect_streambuf.hpp(131) : see reference to class template instantiation 'boost::iostreams::detail::optional<T>' being compiled with [ T=boost::iostreams::detail::concept_adapter<string_source> ] tstIostreams - 3 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

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[range] iterator_range::size() requires a random access iterator?
by Adam Merz 16 Oct '08

16 Oct '08

Why does boost::iterator_range::size() require a random access iterator? The implementation is 'return m_End - m_Begin;' -- if this were changed to 'return std::distance(m_Begin, m_End);' then size() would work with any iterator type. This strikes me as an arbitrary limitation, or at the least a leaky abstraction. Is there a rationale here?

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