August 2013 - Boost-users - lists.preview.boost.org

Boost 1.54.0: libboost_filesystem-vc110-mt-gd-1_54.lib is missing.
by Amann, Julian 19 Aug '13

19 Aug '13

I build boost 1.54.0 this way (Windows 8 with Visual Studio 2012 x64): b2 address-model=64 toolset=msvc-11.0 --build-type=complete stage --with-filesystem --with-signals --with-system \bootstrap.bat I expect to get a file named 'libboost_filesystem-vc110-mt-gd-1_54.lib' (some boost header file is linking this file via #pragma ...) Unfortunately I get only a 'boost_filesystem-vc110-mt-gd-1_54.lib' and a 'libboost_filesystem-vc110-mt-sgd-1_54.lib' Any idea what I am doing wrong? Best regards, Julian

3 2

[AFIO] AFIO Proposed Feature Voting Announcement
by Paul Kirth 19 Aug '13

19 Aug '13

Hello Boost-dev and Boost-users, I’m Paul Kirth, and I am the student working on the upcoming AFIO library this summer as part of GSoC. As of last week AFIO is fully ported to Boost and is now building cleanly on all of the last three major releases of the three most popular C++ compilers. Niall Douglas, my mentor for AFIO, has previously mentioned on the list that we would be asking for your feedback regarding which new features would be most beneficial to the Boost community. We would like to accommodate you all, but with GSoC being limited in time and ending in just one month’s time now, we’re going to limit the current additions to the top 3 most requested features. I plan to stay involved with AFIO for as long as I am able, so I’m sure many more of these features can be supported by AFIO in the future. I have set up a voting site on https://boostafio.uservoice.com to help with the voting. You may vote 10 times as you see fit, and you can give more (or all!) votes to those features you prefer the most. You may also add additional features not currently up for voting, so we encourage you to read the whole list of proposed additions before adding your own. Try to be descriptive with your feature request including a rationale, as not everyone involved with Boost may have the same expertise as you do. Including an example of how this feature would useful will help make a good case for your feature request, and help voters identify what is important. Finally, if you are not familiar with AFIO, we encourage you to take a look at our documentation at https://ci.nedprod.com/view/All/job/Boost.AFIO%20Build%20Documentation/Boos…. A link is also present on the voting site for your convenience. Additionally you will find our project on github at https://github.com/BoostGSoC/boost.afio, if you wish to dive into the source code for yourself. Voting is open right now, so please be sure to vote before the voting period ends on 8/23/13 at 11:59 PM GMT-8:00. We look forward to seeing which features are most important to the community, and hope to meet your expectations. Quick list of the features already proposed: Directory Monitoring Support Permissions and ACL Support Support for Boost Iostreams Improve Formal Closure Execution Engine Support Asynchronous Directory Enumeration Memory Mapped File Support Support for STL Iostreams Linux Kernel AIO Backend POSIX aio_* Asynchronous I/O Backend -- Paul Kirth (310) 709-2516

1 0

[property_thee] Problem parse xml with boost property_thee
by Neo Apostol 19 Aug '13

19 Aug '13

Hello every one. I have xml the same link this http://pastebin.com/SzxuJq71 and I parse it with boost property_thee. I have got problems with media:thumbnail nodes when I wanted to get attributes width and url. Can anyone help me ? Thanks. -- View this message in context: http://boost.2283326.n4.nabble.com/property-thee-Problem-parse-xml-with-boo… Sent from the Boost - Users mailing list archive at Nabble.com.

1 0

question about BOOST_CONCEPT_REQUIRES
by Robert Ramey 18 Aug '13

18 Aug '13

#include "boost/concept/requires.hpp" #include "boost/concept_check.hpp" #include <iterator> template <typename T> BOOST_CONCEPT_REQUIRES(( ((boost::ForwardIterator<T>)) ((boost::LessThanComparable< typename std::iterator_traits<T>::value_type >)) ), (void) ) bubble_sort(T begin, T end); if I compile this with gcc 4.5.3 I get some error messages which I don't expect to see: z:\BoostRelease\libs\serialization\test\test_zmisc.cpp:13:1: error: * cannot appear in a constant-expression z:\BoostRelease\libs\serialization\test\test_zmisc.cpp:13:1: error: a call to a constructor cannot appear in a constant-expression z:\BoostRelease\libs\serialization\test\test_zmisc.cpp:13:1: error: template argument 1 is invalid z:\BoostRelease\libs\serialization\test\test_zmisc.cpp:13:1: error: template argument 1 is invalid z:\BoostRelease\libs\serialization\test\test_zmisc.cpp:14:28: error: invalid type in declaration before ; token Note this occurs even before the template declaration is invoked. Any insight would be appreciated. Robert Ramey

2 2

[math] Solving quadratic, cubic & quartic functions
by Fredrik Orderud 18 Aug '13

18 Aug '13

I've run into an eigenvalue problem where I need to compute the roots of a cubic polynomial. This is a straight-forward problem to solve analytically, but I want to avoid reinventing the wheel if possible. The boost::math doc mentions some root-finding functions, but they all seem to be iterative - which should not be neccesary in my case. Can anyone tell me if boost includes any functions for analytically computing the roots of quadratic, cubic and possibly quartic polynomials? Thanks in advance, Fredrik Orderud

2 2

framework for invoking func-ptrs with different argument numbers
by firespot 18 Aug '13

18 Aug '13

Hi, Consider the following task: Given a -) pointer to a function, and -) an iterator range with elements of type void *, the function-ptr shall be called with all the elements in the range as arguments. So conceptionally something like this: template <typename Func, typename Iter> void make_call(Func, Iter begin, Iter end) { int n = std::distance(begin, end); (*Func) (*(begin), *(begin + 1), *(begin + 2), ..., *(begin + n - 1)) } The interface (function declaration) here is +- what I want, the implementation shown of course is dummy-code not working. Does boost provide a more or less easy way to get this implementation smoothly done? C++ is 2003 version, so code must be compatible with e.g. VS 2008.. Note that I would know in principle a way how to do implement it myself, which involves the creation of a separate class for each number of arguments, but that's precisely what I want to avoid and I hope that wheel has already been invented in some boost-library :) thanks and regards, Thomas

4 3

Boost::MPI Enum Bug
by Barker, Daniel 16 Aug '13

16 Aug '13

Hi All, I am writing some software which is using boost::mpi. I think I have run into a slight bug (or at least a limitation) with the library. It is very similar to this question on S/O: http://stackoverflow.com/questions/8127442/sending-complex-data-with-skelet… I am sending/receiving a class which has an enum member variable. Using normal send and receive was working fine but then I tried to use the skeleton/content mechanism and now my program failed with a segfault on calling `communicator::isend` with the content. While compiling, the compiler issued a warning about an uninitizialized variable: /home/dan/boost_1_54_0/boost/archive/detail/iserializer.hpp:539:9: warning: ‘i’ may be used uninitialized in this function [-Wuninitialized] I looked and noticed this was a function for handling enum values so I commented out the enum variable from my serialization member function and then the sending worked as expected. It looks like the same cause (using addresses of temporaries) as in the S/O question. If anyone is interested I have written a small example exhibiting this issue. I have a couple of questions regarding this: * Is it possible to get around this limitation/bug?^ * Is boost::mpi still being actively developed? I've found a few discussions about this but none really lead anywhere. Thanks, Dan ^ Perhaps it would be possible to write a custom serialize function for any enums but this would be a pain if one used many different enums.

1 0

[container / move] return a container of non-movables from a function in C++03
by Adam Romanek 16 Aug '13

16 Aug '13

Hi, I'd like to return a container of non-movables from a function in C++03 with no success. here is a sample code that does not compile for me: #include <boost/container/vector.hpp> #include <boost/move/utility.hpp> class non_copyable { BOOST_MOVABLE_BUT_NOT_COPYABLE(non_copyable) public: non_copyable(){} non_copyable(BOOST_RV_REF(non_copyable)) {} non_copyable& operator=(BOOST_RV_REF(non_copyable)) { return *this; } }; typedef boost::container::vector<non_copyable> nc_vector; nc_vector create() { return nc_vector(); } int main () { nc_vector v(create()); return 0; } The compiler says: (...) /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: error: passing ‘const non_copyable’ as ‘this’ argument of ‘non_copyable::operator boost::rv<non_copyable>&()’ discards qualifiers [-fpermissive] (...) See below for a full compiler output. I use Boost v1.54 and gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3. Is it a bug? Here is the full compiler output: In file included from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/allocator_traits.hpp:388:0, from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/detail/utilities.hpp:28, from /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/vector.hpp:37, from main.cpp:1: /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp: In static member function ‘static void boost::container::allocator_traits<Alloc>::priv_construct_dispatch2(boost::false_type, Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator<non_copyable>, boost::false_type = boost::integral_constant<bool, false>]’: /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: instantiated from ‘static void boost::container::allocator_traits<Alloc>::priv_construct(boost::true_type, Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator<non_copyable>, boost::true_type = boost::integral_constant<bool, true>]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: instantiated from ‘static void boost::container::allocator_traits<Alloc>::construct(Alloc&, T*, const P0&) [with T = non_copyable, P0 = non_copyable, Alloc = std::allocator<non_copyable>]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/detail/utilities.hpp:555:10: instantiated from ‘typename boost::container::container_detail::disable_if_memcpy_copy_constructible<I, F, F>::type boost::container::uninitialized_copy_alloc_n(A&, I, typename std::iterator_traits<_II>::difference_type, F) [with A = std::allocator<non_copyable>, I = non_copyable*, F = non_copyable*, typename boost::container::container_detail::disable_if_memcpy_copy_constructible<I, F, F>::type = non_copyable*, typename std::iterator_traits<_II>::difference_type = int]’ /home/A.Romanek/tmp/boost/boost_1_54_0/boost/container/vector.hpp:734:7: instantiated from ‘boost::container::vector<T, Allocator>::vector(const boost::container::vector<T, Allocator>&) [with T = non_copyable, Allocator = std::allocator<non_copyable>, boost::container::vector<T, Allocator> = boost::container::vector<non_copyable>]’ main.cpp:16:20: instantiated from here /home/A.Romanek/tmp/boost/boost_1_54_0/boost/preprocessor/iteration/detail/local.hpp:37:1: error: passing ‘const non_copyable’ as ‘this’ argument of ‘non_copyable::operator boost::rv<non_copyable>&()’ discards qualifiers [-fpermissive] WBR, Adam Romanek

5 7

cross-compilation x86_64-w64-ming32: undefined reference to `InterlockedIncrement'
by Frédéric Bron 16 Aug '13

16 Aug '13

Hi, I am trying to cross-compile from linux 64 bits to windows 64 bits. I am using fedora 19 with -std=c++11 and boost 1.53.0 that comes with fedora. The compiler is x86_64-w64-mingw32-g++. The compile flags I use: -O3 -DNDEBUG -DWINDOWS -std=c++11 -Wall -Wextra -pipe -ffloat-store -DBOOST_DISABLE_ASSERTS -DBOOST_FILESYSTEM_VERSION=3 -DBOOST_FILESYSTEM_NO_DEPRECATED -DBOOST_THREAD_USE_LIB and a typical link command: $ x86_64-w64-mingw32-g++ -o foo.exe bar1.o bar2.o -Wl,--enable-auto-import -static -lboost_system-mt -lboost_filesystem-mt -lboost_thread-mt -lboost_chrono-mt -mthreads I then get the following errors (each line multiple times with different .text+0x###): /usr/x86_64-w64-mingw32/sys-root/mingw/lib/../lib/libboost_thread-mt.a(thread.o):(.text+0x286): undefined reference to `InterlockedIncrement' /usr/x86_64-w64-mingw32/sys-root/mingw/lib/../lib/libboost_thread-mt.a(thread.o):(.text+0x3e7): undefined reference to `InterlockedDecrement' /usr/lib64/gcc/x86_64-w64-mingw32/4.8.1/../../../../x86_64-w64-mingw32/bin/ld: /usr/x86_64-w64-mingw32/sys-root/mingw/lib/../lib/libboost_thread-mt.a(thread.o): bad reloc address 0x8 in section `.data' collect2: error: ld returned 1 exit status make: *** [mgw64-release/bin/transpose.exe] Erreur 1 I see that this may come from <boost/detail/interlocked.hpp> but I have no idea what this header is used for. This is what remains after the pre-processor phase (g++ -E): # 1 "/usr/x86_64-w64-mingw32/sys-root/mingw/include/boost/detail/interlocked.hpp" 1 3 4 # 137 "/usr/x86_64-w64-mingw32/sys-root/mingw/include/boost/detail/interlocked.hpp" 3 4 namespace boost { namespace detail { extern "C" long InterlockedIncrement( long volatile * ); extern "C" long InterlockedDecrement( long volatile * ); extern "C" long InterlockedCompareExchange( long volatile *, long, long ); extern "C" long InterlockedExchange( long volatile *, long ); extern "C" long InterlockedExchangeAdd( long volatile *, long ); extern "C" void* InterlockedCompareExchangePointer( void* volatile *, void*, void* ); extern "C" void* InterlockedExchangePointer( void* volatile *, void* ); } } Note that targeting windows 32 bits works allright but the result of the pre-processor phase is slightly different: # 1 "/usr/i686-w64-mingw32/sys-root/mingw/include/boost/detail/interlocked.hpp" 1 3 4 # 137 "/usr/i686-w64-mingw32/sys-root/mingw/include/boost/detail/interlocked.hpp" 3 4 namespace boost { namespace detail { extern "C" __attribute__((dllimport)) long __attribute__((__stdcall__)) InterlockedIncrement( long volatile * ); extern "C" __attribute__((dllimport)) long __attribute__((__stdcall__)) InterlockedDecrement( long volatile * ); extern "C" __attribute__((dllimport)) long __attribute__((__stdcall__)) InterlockedCompareExchange( long volatile *, long, long ); extern "C" __attribute__((dllimport)) long __attribute__((__stdcall__)) InterlockedExchange( long volatile *, long ); extern "C" __attribute__((dllimport)) long __attribute__((__stdcall__)) InterlockedExchangeAdd( long volatile *, long ); } } Frédéric

1 0

Re: [Boost-users] Serialising templates with smart pointers....
by Marcus MacWilliam 16 Aug '13

16 Aug '13

I think my question is how do I add a serialize method to an interface class, which will invoke the serialize method on the derived sub-class. class Interface { public: virtual void aVirtual() = 0; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { call serialize on derived class } }; class Derived : Interface virtual void aVirtual() { // Do something } private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & m_data; } }; -- Marcus A.T MacWilliam, Senior Software Engineer. 1Spatial Ltd. Tel: +44 (0)1223 420414, ext 2289, Mob: +44 (0)7803 706597. E-Mail: marcus.macwilliam(a)1spatial.com Skype:marcus.macwilliam Tennyson House, 7 Cambridge Business Park, Cambridge, CB4 0WZ. Registered in England No. 4785688, VAT Reg. No. 135539408. Website: http://www.1spatial.com/ E-mail: info(a)1spatial.com

2 1