February 2014 - Boost-users - lists.preview.boost.org

Re: [Boost-users] [interprocess] Shared memory object
by Ahmed Charles 24 Feb '14

24 Feb '14

Windows doesn't have to write to disk if there is no memory pressure in the case of a page file but if you have an explicit file being mapped, then you'll get writes to disk. This hypothesis should be easy to observe by monitoring the disk activity during your perf tests. ________________________________ From: Davies, John Sent: 2/21/2014 1:28 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [interprocess] Shared memory object >From my reading, the Windows version is faster but it doesn't have the persistence as the Linux version. The description mentions this: A class that wraps the native Windows shared memory that is implemented as a file mapping of the paging file. Unlike shared_memory_object<http://www.boost.org/doc/libs/1_55_0/doc/html/boost/interprocess/shared_mem…>, windows_shared_memory<http://www.boost.org/doc/libs/1_55_0/doc/html/boost/interprocess/windows_sh…> has no kernel persistence and the shared memory is destroyed when all processes destroy all their windows_shared_memory<http://www.boost.org/doc/libs/1_55_0/doc/html/boost/interprocess/windows_sh…> objects and mapped regions for the same shared memory or the processes end/crash. Boost lets you choose what means more to you. ___________________________________ John Davies Contractor Home Respiratory Care Philips Home Healthcare Solutions 1740 Golden Mile Highway Monroeville, PA 15146 Email: john.davies(a)philips.com Fax: 724-387-4109 From: Boost-users [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Patrick Steele Sent: Thursday, February 20, 2014 11:40 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [interprocess] Shared memory object Tests at the time were showing the Windows version to operate about twice as fast. If nothing has changed I guess I will remain with it then. I had just been hoping for the code to be more platform dependent. On 20 February 2014 14:44, Ion Gaztañaga <igaztanaga(a)gmail.com<mailto:igaztanaga@gmail.com>> wrote: El 20/02/2014 11:42, Patrick Steele escribió: Hi, can anyone tell me if there is a performance or other difference between boost::interprocess::shared_memory_object and boost::interprocess::windows_shared_memory? With the version of boost we were using back in 2011 ( boost 1.48 ), we found that windows_shared_memory operated faster than shared_memory_object when transporting around 10MB of data. Is this still the case? Thanks, Nothing has changed AFAIK. shared_memory_object is a memory mapped file whereas windows_shared_memory is backed by the pagefile. I don't know why Windows should make one faster than the other, though. Best, Ion _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org<mailto:Boost-users@lists.boost.org> http://lists.boost.org/mailman/listinfo.cgi/boost-users ________________________________ The information contained in this message may be confidential and legally protected under applicable law. The message is intended solely for the addressee(s). If you are not the intended recipient, you are hereby notified that any use, forwarding, dissemination, or reproduction of this message is strictly prohibited and may be unlawful. If you are not the intended recipient, please contact the sender by return e-mail and destroy all copies of the original message. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[iostreams] gzip problem
by Olaf Krzikalla 24 Feb '14

24 Feb '14

Hi @boost, I have a file format containing chunks of gzipped data (using gzip_decompressor/gzip_compressor). Inbetween these chunks there is other (plain) data. So can keep the archive seekable. However apparently this doesn't work out as it should. Whenever gzip_decompressor reaches the end of a chunk it throws an exception. The trouble-making line is in basic_gzip_decompressor::read: if (footer_.done()) { if (footer_.crc() != this->crc()) boost::throw_exception(gzip_error(gzip::bad_crc)); int c = boost::iostreams::get(peek); if (traits_type::is_eof(c)) { ----------------------------- state_ = s_done; } else { peek.putback(c); base_type::close(peek, BOOST_IOS::in); state_ = s_start; header_.reset(); footer_.reset(); } } Thus after the footer is read and checked, the decompressor checks whether or not eof is reached. Obvisiously this isn't the case here - the decompressed chunk is just embedded in the file. Thus the decompressor restarts, but cannot find another header thus throwing an exception. Would it be reasonable to just insert a break? header_.reset(); footer_.reset(); + break; } } This would solve _my_ problem. Or is there another way to work around this issue? Best Olaf

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boost serialize, exception "eaten" up...
by Robert Bielik 23 Feb '14

23 Feb '14

Hi all, I'm trying to make a deserialization user cancellable, and I thought, hey, if I throw an exception in a progress handler (used when reading chars from input stream), that would propagate through the load hieararchy and I can catch it at top level... Nope... it gets caught in iostream (VS2012, row 776) :( , so the _CATCH_IO_END is probably a catch(...). Not very nice, and quite counter-productive if you ask me. Any ideas how to get that exception out ? Regards /Robert

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Build errors trying to build Boost with mingw-w64
by Da-Huntha 22 Feb '14

22 Feb '14

Hey all, I've been trying to build all Boost libraries with mingw-w64 on Windows 8 but some fail. I'm trying to build a 32bit windows release build. The following errors are an excerpt of all the build errors: >d:\win-builds-32\i686-w64-mingw32\include\dvec.h: In function 'F64vec2 IntToF64vec2(const >F64vec2&, int)': >d:\win-builds-32\i686-w64-mingw32\include\dvec.h:840:80: error: '_mm_cvtsi32_sd' was not declared in this scope > inline F64vec2 IntToF64vec2(const F64vec2 &a,int b) { return _mm_cvtsi32_sd(a,b >); } > >^ >In file included from ./boost/system/system_error.hpp:14:0, > from ./boost/thread/exceptions.hpp:22, The build is invoked with: >set PATH=%MINGW_HOME%\bin;%WINDDK_HOME%\7600.16385.1\bin\x86 >bjam toolset=gcc variant=release threading=multi link=static address-model=32 Does anyone understand why these errors are given? Am I missing some configuration?

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[mpl][type_traits] Transforming to common type
by Bjorn Reese 22 Feb '14

22 Feb '14

Given a type T, I am trying to transform a type list into another containing the common type between T and the individual types in the type list. When I compile the example below, I get the following error: /usr/local/include/boost/type_traits/common_type.hpp:111:42: error: incompatible operand types ('mpl_::arg<1>' and 'int') typedef decltype(declval<bool>() ? declval<T>() : declval<U>()) type; ^ ~~~~~~~~~~~~ ~~~~~~~~~~~~ It appears that the placeholder is not expanded to its actual type. If I use, say, decay<> instead of common_type<>, the example works just fine. Does anybody know how I can make it work? Example code: #include <boost/mpl/vector.hpp> #include <boost/mpl/transform.hpp> #include <boost/type_traits/common_type.hpp> int main() { typedef boost::mpl::vector<int, double> sequence_types; typedef boost::mpl::transform< sequence_types, // This is causing the problem boost::common_type<boost::mpl::_1, int>::type >::type transformed_types; return 0; }

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[geometry] boost 1.55, VC++2013 update 1 Build fail
by 乔志强 22 Feb '14

22 Feb '14

I create a Visual Studio 2013 update 1 VC++ Win32 Console Application project, and copy the example from boost_1_55_0\libs\geometry\doc\html\geometry\spatial_indexes\rtree_examples\quick_start.html to a file(delete all codes first), set Precompiled Headers to Not Using Precompiled Headers, then build. But build failed. I change the platform toolset from Visual Studio 2013 (v120) to Visual Studio 2010 (v100), then build successfully. Is it a bug ? Visual Studio 2013 (v120) error message: 1>------ Rebuild All started: Project: ConsoleApplication1, Configuration: Debug Win32 ------ 1> ConsoleApplication1.cpp 1>c:\users\qiaozhiqiang\documents\visual studio 2013\projects\consoleapplication1\consoleapplication1\consoleapplication1.cpp(30): warning C4244: 'argument' : conversion from 'unsigned int' to 'const float', possible loss of data 1>d:\qzq\boost_1_55_0\boost\intrusive\detail\has_member_function_callable_with.hpp(200): error C2228: left of '.select_on_container_copy_construction' must have class/struct/union 1> type is 'boost::move_detail::add_rvalue_reference<U>::type' 1> d:\qzq\boost_1_55_0\boost\intrusive\detail\has_member_function_callable_with.hpp(276) : see reference to class template instantiation 'boost::container::container_detail::has_member_function_callable_with_select_on_container_copy_construction_impl<Fun,true,>' being compiled 1> with 1> [ 1> Fun=std::allocator<boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>> 1> ] 1> d:\qzq\boost_1_55_0\boost\container\allocator_traits.hpp(262) : see reference to class template instantiation 'boost::container::container_detail::has_member_function_callable_with_select_on_container_copy_construction<const Alloc,>' being compiled 1> with 1> [ 1> Alloc=std::allocator<boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\detail\rtree\node\node_d_mem_dynamic.hpp(257) : see reference to class template instantiation 'boost::container::allocator_traits<AllocNode>' being compiled 1> with 1> [ 1> AllocNode=std::allocator<boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\detail\rtree\node\node_d_mem_dynamic.hpp(320) : see reference to function template instantiation 'BaseNodePtr boost::geometry::index::detail::rtree::create_dynamic_node<BaseNodePtr,boost::geometry::index::detail::rtree::dynamic_leaf<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag>>::apply<std::allocator<_Other>>(AllocNode &)' being compiled 1> with 1> [ 1> BaseNodePtr=boost::geometry::index::detail::rtree::dynamic_node<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> * 1> , Value=std::pair<box,unsigned int> 1> , Parameters=boost::geometry::index::quadratic<16,4> 1> , Box=boost::geometry::model::box<point> 1> , Allocators=boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> , _Other=boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> , AllocNode=std::allocator<boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\detail\rtree\node\node_d_mem_dynamic.hpp(320) : see reference to function template instantiation 'BaseNodePtr boost::geometry::index::detail::rtree::create_dynamic_node<BaseNodePtr,boost::geometry::index::detail::rtree::dynamic_leaf<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag>>::apply<std::allocator<_Other>>(AllocNode &)' being compiled 1> with 1> [ 1> BaseNodePtr=boost::geometry::index::detail::rtree::dynamic_node<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> * 1> , Value=std::pair<box,unsigned int> 1> , Parameters=boost::geometry::index::quadratic<16,4> 1> , Box=boost::geometry::model::box<point> 1> , Allocators=boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> , _Other=boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> , AllocNode=std::allocator<boost::geometry::index::detail::rtree::dynamic_leaf<std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\detail\rtree\node\node_d_mem_dynamic.hpp(316) : while compiling class template member function 'boost::geometry::index::detail::rtree::dynamic_node<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag> *boost::geometry::index::detail::rtree::create_node<Allocators,boost::geometry::index::detail::rtree::dynamic_leaf<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag>>::apply(Allocators &)' 1> with 1> [ 1> Value=std::pair<box,unsigned int> 1> , Parameters=boost::geometry::index::quadratic<16,4> 1> , Box=boost::geometry::model::box<point> 1> , Allocators=boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\rtree.hpp(1267) : see reference to function template instantiation 'boost::geometry::index::detail::rtree::dynamic_node<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag> *boost::geometry::index::detail::rtree::create_node<Allocators,boost::geometry::index::detail::rtree::dynamic_leaf<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag>>::apply(Allocators &)' being compiled 1> with 1> [ 1> Value=std::pair<box,unsigned int> 1> , Parameters=boost::geometry::index::quadratic<16,4> 1> , Box=boost::geometry::model::box<point> 1> , Allocators=boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\rtree.hpp(1267) : see reference to class template instantiation 'boost::geometry::index::detail::rtree::create_node<boost::geometry::index::detail::rtree::allocators<std::allocator<Value>,Value,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag>,boost::geometry::index::detail::rtree::dynamic_leaf<Value,Parameters,Box,Allocators,boost::geometry::index::detail::rtree::node_d_mem_static_tag>>' being compiled 1> with 1> [ 1> Value=value 1> , Parameters=boost::geometry::index::quadratic<16,4> 1> , Box=boost::geometry::model::box<point> 1> , Allocators=boost::geometry::index::detail::rtree::allocators<std::allocator<value>,std::pair<box,unsigned int>,boost::geometry::index::quadratic<16,4>,boost::geometry::model::box<point>,boost::geometry::index::detail::rtree::node_d_mem_static_tag> 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\rtree.hpp(1264) : while compiling class template member function 'void boost::geometry::index::rtree<value,boost::geometry::index::quadratic<16,4>,boost::geometry::index::indexable<Value>,boost::geometry::index::equal_to<Value>,std::allocator<Value>>::raw_create(void)' 1> with 1> [ 1> Value=value 1> ] 1> d:\qzq\boost_1_55_0\boost\geometry\index\rtree.hpp(544) : see reference to function template instantiation 'void boost::geometry::index::rtree<value,boost::geometry::index::quadratic<16,4>,boost::geometry::index::indexable<Value>,boost::geometry::index::equal_to<Value>,std::allocator<Value>>::raw_create(void)' being compiled 1> with 1> [ 1> Value=value 1> ] 1> c:\users\qiaozhiqiang\documents\visual studio 2013\projects\consoleapplication1\consoleapplication1\consoleapplication1.cpp(24) : see reference to class template instantiation 'boost::geometry::index::rtree<value,boost::geometry::index::quadratic<16,4>,boost::geometry::index::indexable<Value>,boost::geometry::index::equal_to<Value>,std::allocator<Value>>' being compiled 1> with 1> [ 1> Value=value 1> ] ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ========== consoleapplication1.cpp, line 24 is: bgi::rtree< value, bgi::quadratic<16> > rtree;

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[interprocess] Shared memory object
by Patrick Steele 21 Feb '14

21 Feb '14

Hi, can anyone tell me if there is a performance or other difference between boost::interprocess::shared_memory_object and boost::interprocess::windows_shared_memory? With the version of boost we were using back in 2011 ( boost 1.48 ), we found that windows_shared_memory operated faster than shared_memory_object when transporting around 10MB of data. Is this still the case? Thanks, Patrick

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Gsoc
by Anulesh Tiwari 21 Feb '14

21 Feb '14

I've been looking at the various projects and the previous years project . I came across the boost.ublas project that was offered last year . This project seems very cool . Is the project going to be offered again ? The idea of adding additional protocols or modifying existing protocols sounds fun . There will be very likely a project proposal for the boost.ublas project, content will be very similar :) I would love to get a better feel about the entire boost project . Any pointers on how to do the same would be very helpful.

1 1

Build problems with 64-bit VC12 (MSVS2013)
by Craig Henderson 21 Feb '14

21 Feb '14

Hi all, I am having trouble building Boost 1.55 for x64 using VC12. 32-bit builds without error, but 64-bit fails. All of the errors are boost/archive/iterators/transform_width.hpp(151) : error C2039: 'min' : is not a member of 'std' and repeats a lot I added #include <algorithm> to the beginning of the transform_width.hpp header file, and the build now completes without error. However, my app has two linker errors linking with libboost_system-vc120-mt-1_55.lib features.obj : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::system_category(void)" (?system_category@system@boost@ @YAAEBVerror_category@12@XZ) referenced in function "public: __cdecl boost::system::error_code::error_code(void)" (??0error_code@system@boost@ @QEAA@XZ) features.obj : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::generic_category(void)" (?generic_category@system@boost@ @YAAEBVerror_category@12@XZ) referenced in function "void __cdecl boost::system::`dynamic initializer for 'errno_ecat''(void)" (??__Eerrno_ecat@system@boost@@YAXXZ) Again, the 32 bit builds and links Ok. I'm thinking that as the problematic file in Boost in is an 'archive' directory, perhaps the wrong include file is being picked up? But I can't find the difference in 32/64 configurations to find the cause. Is this a known problem? Any suggestions how to diagnose or (preferably!) fix this? Many thanks Craig

1 0

Where is BOOST_TEST - the universal testing tool
by Adi Shavit 21 Feb '14

21 Feb '14

Hi, I read here<http://boost.2283326.n4.nabble.com/test-BOOST-TEST-universal-testing-tool-t…>and here <http://lists.boost.org/Archives/boost/2013/09/206202.php>about BOOST_TEST - the universal testing tool. Where can I find it? Is it still not part of the library? Thanks, Adi

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template trick
by gast128 20 Feb '14

20 Feb '14

I recently watched Stephen Lavavej's excellent channel9 video 'Core C++, 2 of n' in which he described a nice trick to stop template argument deduction: template <typename T> void (T t1, typename std::identity<T>::type t2) { } Browsing the internet for a similar problem, I recently discovered that Peter Dimov already described this trick in 2002 in 'Template function type inference with references' comp.lang.c++.moderated. Boost is more for the libraries, but could it also reserve some space for documenting these template tricks?

4 3

Should boost libs be rebuilt after applying patch?
by qplace 19 Feb '14

19 Feb '14

boost 1.55 I had to apply the patch defined in Ticket #9369 to the boost source file. I did it after libraries were built. Should I now rebuild the libraries again?

3 5

path of test-binary
by dib 19 Feb '14

19 Feb '14

Hi, how can I get the path where b2 placed the binaries of boost tests? Problem is the following: some of the tests need the path to a shared library, which is built together with the tests. in the lib/mylib/tests/Jamfile.v2 I have the following: [...] # our test lib for shared library tests lib test_library : test_library.cpp ; test-suite mylib : # # shared library # [ run shared_library_load_test.cpp ] [ run shared_library_get_symbol_test.cpp ] # # [...] Inside shared_library_*_test.cpp I need something like this: boost::filesystem::path tstlib("bin.v2/libs/mylib/test/mycompiler/test_library.so"); As boost.build decides by itself where to put the binary, i cannot hardcode the path in the source-files.. Is there a way to get the path from boost.build? If not, how could I solve this problem? -- regards dib

3 2

Unit Tests and function calling
by Charles Yates 19 Feb '14

19 Feb '14

Hi, Just wanted a second opinion on how best to handle calling functions which invoke BOOST_REQUIRE and BOOST_CHECK type logic. For example, if I have a test like: void stuff( ... ) { BOOST_REQUIRE( ... ); BOOST_CHECK( ... ); } BOOST_AUTO_TEST( check_stuff ) { stuff( case1 ); stuff( case2 ); stuff( case3 ); } in the CLF log case at least, I only see which lines in stuff failed, but not which which case. I can change things so that we have: bool stuff( ... ) { bool result = true; if ( ( result = require-predicate ) == true ) result = check-predicate; return result; } BOOST_AUTO_TEST( check_stuff ) { BOOST_CHECK( stuff( case1 ) ); BOOST_CHECK( stuff( case2 ) ); BOOST_CHECK( stuff( case3 ) ); } but then I lose the info in the logs over which predicates are failing and it's generally a bit nasty :). As a result, I've been playing with this which seems to encapsulate things pretty well for me (though may introduce more parenthesis than is strictly necessary and may introduce shadowed variables and other issues?): #define BOOL_CHECK( result, pred ) { bool pred_result; BOOST_CHECK( pred_result = ( pred ) ); result = pred_result && result; } #define BOOL_REQUIRE( pred ) { bool pred_result; BOOST_CHECK( pred_result = ( pred ) ); if ( !pred_result ) return pred_result; } #define BOOL_REQUIRE_EQUAL( name, value ) { bool pred_result; BOOST_CHECK( pred_result = ( ( name ) == ( value ) ) ); if ( !pred_result ) return pred_result; } void stuff( ... ) { bool result = true; BOOL_REQUIRE( ... ); BOOL_CHECK( result, ... ); return result; } BOOST_AUTO_TEST( check_stuff ) { BOOST_CHECK( stuff( case1 ) ); BOOST_CHECK( stuff( case2 ) ); BOOST_CHECK( stuff( case3 ) ); } when one of the predicates fails, I get 2 errors in the log - the first being the specific line in 'stuff' and the second being failing case. I've only tested it with g++ and don't know if it's a sensible approach - wondered if any of you guys had any suggestions? Cheers, Charlie

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[BGL] isomorphism: how to define vertex invariant
by Pablo Madoery 19 Feb '14

19 Feb '14

Hi, I have two graphs and I want to know if they are isomorphic. I adjunct the graphs in .png. I read the documentation but i can't figure out how i must define the vertex invariant correctly. what I want is to consider that two graph are not isomorphic taking count of the vertices ids (the unsigned int value that they have). In the example i give I want the function isomorphism to return false. actually it return true. Thank you ! //////////////////////////////////////////////////////////////////////////////////////////// Graph graph1; Graph::vertex_descriptor aA = add_vertex(graph1); Graph::vertex_descriptor bA = add_vertex(graph1); Graph::vertex_descriptor cA = add_vertex(graph1); Graph::edge_descriptor edA1 = (add_edge(aA, bA, graph1)).first; Graph::edge_descriptor edA2 = (add_edge(bA, cA, graph1)).first; graph1[edA1].weight = 1; graph1[edA2].weight = 2; //////////////////////////////////////////////////////////////////////////////////////////// Graph graph2; Graph::vertex_descriptor aB = add_vertex(graph2); Graph::vertex_descriptor bB = add_vertex(graph2); Graph::vertex_descriptor cB = add_vertex(graph2); Graph::edge_descriptor edB1 = (add_edge(bB, aB, graph2)).first; Graph::edge_descriptor edB2 = (add_edge(aB, cB, graph2)).first; graph2[edB1].weight = 1; graph2[edB2].weight = 2; /////////////////////////////////////////////////////////////////////////////////////////// bool isIso = boost::isomorphism(graph1, graph2);

1 0

Meeting C++ 2014 - Call for Papers
by Jens Weller 19 Feb '14

19 Feb '14

Hello boost community, Meeting C++ 2014 has been announced today, it will be in Berlin on the 5th and 6th December! More details on the conference in the official announcement: http://meetingcpp.com/index.php/newsreader/items/announcing-meeting-c-2014-… With the announcement, also the call for paper is now again open till April 20th. This years theme track of the conference is "Scientific Programming with C++". I'm looking for a diverse set of talks about C++, talks about boost, Qt, STL, any libraries, testing, the C++ language (C++11/14/1y) or any other C++ related topic. More details on the call for papers: http://meetingcpp.com/index.php/newsreader/items/call-for-papers-meeting-c-… Kind regards, Jens Weller

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Fatal runtime error when using Boost in a native static library referenced by a mixed dll
by Dario Ramos 19 Feb '14

19 Feb '14

I refactored a native C++ static library to use boost::thread and boost::asio instead of the Windows API. This static library is referenced by a C++/CLI dll built with the /clr switch; it acts as a wrapper for the managed upper layers to use. I use Boost inside native C++ dlls referenced by C++/CLI dlls and that works fine, but this particular scenario is a first. I suspect that Boost and C++/CLI don't play nice together, since I had to be careful to use the PIMPL idiom to avoid boost headers from being indirectly included in C++/CLI code. But now that I have to forcibly link a Boost lib with my C++/CLI dll, things have gone awry. Is this a supported usage for Boost? My environment: Boost 1.53.0, Visual Studio Professional 2012 Version 11.0.61030.00 Update 4, Windows 7 x64. The error is an EEFileLoadException in KernelBase.dll. It happens right after my C++/CLI dll is loaded into memory. Here's the callstack: > KernelBase.dll!_RaiseException@16() + 0x58 bytes msvcr110_clr0400.dll!__CxxThrowException@8() + 0x3e bytes clrjit.dll!Compiler::impResolveToken() + 0x3a bytes clrjit.dll!Compiler::impImportBlockCode() + 0x10d5 bytes clrjit.dll!Compiler::impImportBlock() + 0x55 bytes clrjit.dll!Compiler::impImport() + 0x167 bytes clrjit.dll!Compiler::compCompile() + 0x47 bytes clrjit.dll!Compiler::compCompileHelper() + 0x1f0 bytes clrjit.dll!Compiler::compCompile() + 0x104 bytes clrjit.dll!jitNativeCode() - 0x11eb bytes clrjit.dll!CILJit::compileMethod() + 0x25 bytes [External Code] mscoreei.dll!__CorExeMain@0() + 0x71 bytes mscoree.dll!_ShellShim__CorExeMain@0() + 0x227 bytes mscoree.dll!__CorExeMain_Exported@0() + 0x8 bytes ntdll.dll!___RtlUserThreadStart@8() + 0x27 bytes ntdll.dll!__RtlUserThreadStart@8() + 0x1b bytes -- *Darío Eduardo Ramos* Meditech S.A. www.meditech.com.ar (+54) 01147603300, Interno 31 Av. Julio A. Roca 3456 Florida Oeste, Bs.As. Argentina

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[config] Macro to detect no implicitly movable?
by TONGARI J 19 Feb '14

19 Feb '14

Hi, Some compilers support r-value reference while not providing implicitly-defined move ctor/assign (e.g. VC10), is there a way to detect this defect? Macro like BOOST_NO_IMPLICITLY_MOVABLE would be helpful. Is "defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)" good enough? Thanks,

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finite state filters controlled ...
by raespi 19 Feb '14

19 Feb '14

Boost hi .. I'm using the finite state filter component in the iostreams library to create a state machine that can easily help me process incoming data streams from various medical sensors. I'm currently working around the following scenarios and wanted to run them by the list to see if the method I chose was the preferred one. 1- Constant datastream with no variation in datagrams. Solution: use finite state filters as they come, works ok ! 2- Variable datastreams with constant size in datagrams. Solution: use finite state filters with a transition table that can interpret anything and choosing in the processing function the right way to go, not very clean, but works !! 3- Variable datastreams with variable sizes. Solution: trying to change the finite state filter on the go, currently doesn't work. I noticed that when bytes are inserted into the state machine these don't get processed until a certain buffer size is met internally, resulting in a behaviour where data gets analyzed long after it has been inserted. I saw that the flush() function for the iostream that contains de state machine suffices when called before inserting a new character with a line such as: io::flush<io::filtering_ostream> ( this->data ); but the problem is that the only mechanism that can determine when a whole package has been received and one can change state machines to analyze a new state lies within the state machine itself (in the processing functions), I can't issue a flush() from within a state machine since it won't execute until a specific buffer size is met. Any ideas on how to go around this matter ?? I'm currently using boost 1.53 on Linux Thanks ...

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[lexical_cast] Why isn't boost::lexical_cast bijective?
by Egor Tensin 19 Feb '14

19 Feb '14

Why this works: boost::lexical_cast<std::string>((void *) 42UL) and this throws: boost::lexical_cast<void*>(boost::lexical_cast<std::string>((void*) 42UL)) while converting void* to std::string and vice versa works perfectly using std:: streams?

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Fedora upgrade - missing Boost multi-threaded libraries
by David Aldrich 18 Feb '14

18 Feb '14

Hi We have just upgraded a Fedora machine from Fedora 19 (boost 1.53) to Fedora 20 (boost 1.54). We notice that the Boost -mt libraries have disappeared. Please can anyone explain this and tell me how to install the -mt libraries? Best regards David

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[log] Qt integration
by Olivier Tournaire 18 Feb '14

18 Feb '14

Hi all, I would like to use boost::log within a Qt based application. For now, I simply want to redirect the output of BOOST_LOG_TRIVIAL(xxx) macro to a QTextEdit. What is the easiest way to do that? Is there a way to get the logger output string? Best regards

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[Units] Un-scaling dimensionless value
by Lindley French 18 Feb '14

18 Feb '14

I am using Boost.Units to try and compute the number of samples in a time interval, given the sample rate. Given this code: typedef make_scaled_unit<si::frequency, scale<10, static_rational<3> > >::type kilohertz_unit; typedef make_scaled_unit<si::time, scale<10, static_rational<-6> > >::type microseconds_unit; <code> template <typename T=unsigned> using Kilohertz = quantity<kilohertz_unit,T>; template <typename T=unsigned> using Microseconds = quantity<microseconds_unit,T>; // Using boost::rational as the value type neatly avoids overflows Kilohertz<rational<unsigned>> sample_rate(125*si::kilo*si::hertz); Microseconds<rational<unsigned>> duration(10*si::seconds); auto total = sample_rate*duration; </code> Now, when I cout these values, I see that everything is technically the correct. The problem is that total is a dimensionless quantity which is scaled----it's 1,250,000,000, when I expect 1,250,000, and it displays as "1250000000 m", where m is "milli", not "meters". What is the correct way to un-scale dimensionless quantities? I tried this: quantity<si::dimensionless,rational<unsigned>> unscaled(total); However, unscaled still has the same value. I also tried typedef make_scaled_unit<si::dimensionless, scale<10, static_rational<0> > >::type dimensionless_unit; quantity<dimensionless_unit,rational<unsigned>> unscaled(total); but this time, unscaled came out zero. Any suggestions?

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[units] slowness dimension
by Michael Powell 18 Feb '14

18 Feb '14

Hello, I've learned about a "new" (or potentially new-to-boost-units, at any rate) dimension this week. TBD whether we'll be using boost or even units, but in the event we would, I'd like to add a slowness dimension. Basically it is the inverse of velocity: where velocity is time per length, slowness is length per time. Taking a gander at the velocity.hpp physical dimension, doesn't seem like a terribly hard thing to do, and with the new Git-module decomp, even less so today? Thank ye... Best regards, Michael Powell

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[fusion][?] a dictionary with compile time (or types as) keys
by Nick Stokes 17 Feb '14

17 Feb '14

The problem is the following: class TypeDictionary { public: // implementation be here -- and the question is about this }; struct Foo; struct Bar; void userOfTypeDictionary() { TypeDictionary td; td.insert( Foo() ); td.insert( Bar() ); td,insert( double(3.14) ); // and other unknown (to TypeDictionary) // list of types attached // later on, in a different scope perhaps Foo& f = td.get<Foo>() ; Bar& f = td.get<Bar>(); double pi = tg.get<double>(); // ... } Now the question so far seems like right up in the alley of Boost.Fusion, perhaps with a boost::fusion::set, but I am unsure how to manipulate a set of types unknown ahead of time as in code above, and with a -- rather obvious -- extension whereby different instances of TypeDictionary would be used to contain a different set of types, potentially in different compilation units. As for a realistic motivating use case, think of a plugin manager. At any given time of its life an arbitrary heterogeneous set of objects are attached to it, and the it is the manager's job to manage the life time of the attached objects and return (a reference) to them when queried in a type-safe manner. Any ideas on whether such a thing is possible, and how, would be deeply appreciated. Thanks many, Nick

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