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Graph: 2 questions on property maps and subgraphs
by Andrea Olgiati 13 Jan '05

13 Jan '05

Hi, A couple of (newbie) questions on subgraphs and property maps: 1. I tried to re-run the example posted at http://lists.boost.org/MailArchives/boost-users/msg05889.php and I get a segfault whilst trying to assign name1[B1] - according to a follow-up message (http://lists.boost.org/MailArchives/boost-users/msg05891.php) that code snippet was supposed to be working fine. Am I doing something wrong? 2. Maybe it's another symptom of the same problem, but I am seeing runtime failures (invalid pointers) when I write code such as: > Graph *graph = wantFullGraph? rootGraph : subGraph; > MyPropertyMap mymap = get(my_type_t(), *graph); > for( v in all vertices in *graph) { > mymap[v] = blah; > } That is, after reading the docs my understanding is that if I pick up a property map from a (sub)graph, I can use the vertices in that (sub)graph to address into that map - everything should work fine provided that I am consistently using the same (sub)graph. Is this understanding correct? If so, I'm puzzled - the only way I can get this to work is to do: > Graph *graph = wantFullGraph? rootGraph : subGraph; > MyPropertyMap mymap = get(my_type_t(), *rootGraph); > for( v in all vertices in *graph) { > v1 = graph->local_to_global(v) > mymap[v1] = blah; > } I am using - gcc version 3.3.4 (pre 3.3.5 20040809) - Linux myhost 2.6.8-24.10-default #1 Wed Dec 22 11:54:27 UTC 2004 i686 i686 i386 GNU/Linux Can someone enlighten me. please? Thanks, Andrea

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Serialazation compilign under windows.
by Ken Perry 12 Jan '05

12 Jan '05

I am trying to compile Serialization with out cygwin but serialization and other libraries in boost give the error "#error wide char i/o not supported on this platform" When I try to compile under the xp pro Command line. Is there some way this and the other libraries can be compiled under Mingw even if wide char i/o is not supported I don't really need wide char i/o I just want a way to use serialization xml as my base file types under both linux and windows. Ken

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more matrix.hpp
by Becky Bendick 12 Jan '05

12 Jan '05

Here is a more detailed description of the error from the config.log /sw/include/boost/numeric/ublas/vector_expression.hpp:1837: error: due to a defect in the G++ 3.2 ABI, G++ has assigned the same mangled name to two different types In file included from /sw/include/boost/numeric/ublas/matrix.hpp:23, from conftest.cc:67: /sw/include/boost/numeric/ublas/matrix_expression.hpp:5156: error: due to a defect in the G++ 3.2 ABI, G++ has assigned the same mangled name to two different types Thanks again, Becky ------------------------------------------------------------------------ ---------------------- Rebecca Bendick, Ph.D. Bullard Laboratories University of Cambridge Madingley Road CAMBRIDGE CB3 0EZ United Kingdom bendick(a)esc.cam.ac.uk

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C++ Template Metaprogramming - Exercise 2-0
by Trask, Bruce (US SSA) 12 Jan '05

12 Jan '05

Hello, I am going through the book C++ Template Metaprogramming and wanted a sanity check on Exercise 2-0 from the book. My first question is: What would be a motivating example for why one would want a add_const_ref<T> metafunction that returned T if it was a reference and T const& otherwise? My second question is: How did I do? My guess is that the second crack is more correct. Here is crack one: My first crack at the exercise is below (my 2nd crack is below that) #include <iostream> #include <boost/type_traits/is_reference.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/static_assert.hpp> using namespace std; template<typename T, bool> struct add_const_ref { typedef T const& value_type; }; template<typename T> struct add_const_ref<T, true> { typedef T value_type; }; template<typename T> void func(typename add_const_ref<T, boost::is_reference<T>::value >::value_type t) { // .. do something } class BigClass { }; int main() { int i = 0; BOOST_STATIC_ASSERT((boost::is_same<add_const_ref<int&, boost::is_reference<int&>::value >::value_type, int&>::value)); BOOST_STATIC_ASSERT((boost::is_same<add_const_ref<int, boost::is_reference<int>::value >::value_type, int const&>::value)); func<int&>(i); BigClass myBigClass; func<BigClass>(myBigClass); return 0; } After taking a look at add_reference.hpp in boost I modified my answer to the one below: #include <iostream> #include <boost/type_traits/is_reference.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/static_assert.hpp> using namespace std; template<bool> struct const_ref_adder { template<typename T> struct result_ { typedef T const& value_type; }; }; template<> struct const_ref_adder<true> { template<typename T> struct result_ { typedef T value_type; }; }; template<typename T> struct add_const_ref { typedef typename const_ref_adder<boost::is_reference<T>::value >::template result_<T>::value_type value_type; }; template<typename T> void func(typename add_const_ref<T>::value_type t) { // .. do something } class BigClass { }; int main() { int i = 0; BOOST_STATIC_ASSERT((boost::is_same<add_const_ref<int&>::value_type, int&>::value)); BOOST_STATIC_ASSERT((boost::is_same<add_const_ref<int>::value_type, int const&>::value)); func<int&>(i); BigClass myBigClass; func<BigClass>(myBigClass); return 0; } Thanks in advance for your input, Bruce

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matrix.hpp usability
by Becky Bendick 12 Jan '05

12 Jan '05

Hi, I guess this is a 'newbie' question, so I apologize if the answer is obvious to everyone but me. I've just installed boost 1.31 on an apple powerpc using fink. However, when I run compile for the dependent software that needs the boost libraries, I get the following: checking for boost/numeric/ublas/matrix.hpp presence in /sw/include...... yes checking for boost/numeric/ublas/matrix.hpp usability...... no Is there something I can do to matrix.hpp to make it usable? I've confirmed that it exists in the right place, and isn't empty or anything. Thanks, Becky ------------------------------------------------------------------------ ---------------------- Rebecca Bendick, Ph.D. Bullard Laboratories University of Cambridge Madingley Road CAMBRIDGE CB3 0EZ United Kingdom bendick(a)esc.cam.ac.uk

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Serialization polymorphic iarchives & binary_object problem
by Sergey Skorniakov 12 Jan '05

12 Jan '05

Hello, All! This code: #include <fstream> #include <boost/archive/polymorphic_text_iarchive.hpp> #include <boost/archive/polymorphic_text_oarchive.hpp> #include <boost/archive/polymorphic_binary_iarchive.hpp> #include <boost/archive/polymorphic_binary_oarchive.hpp> #include <boost/serialization/binary_object.hpp> int main(int argc, char* argv[]) { { char testdata[4] = "asd"; std::ofstream os("test.txt", std::ios::binary); boost::archive::polymorphic_binary_oarchive ar(os); // boost::archive::polymorphic_text_oarchive ar(os); // boost::archive::text_oarchive ar(os); // boost::archive::binary_oarchive ar(os); ar & boost::serialization::make_binary_object(&testdata, sizeof(testdata)); assert(os.good()); } { char testdata[4] = " "; std::ifstream is("test.txt", std::ios::binary); assert(is.good()); boost::archive::polymorphic_binary_iarchive ar(is); // boost::archive::polymorphic_text_iarchive ar(is); // boost::archive::text_iarchive ar(is); // boost::archive::binary_iarchive ar(is); ar & boost::serialization::make_binary_object(&testdata, sizeof(testdata)); assert(is.good()); assert(testdata[0] == 'a'); } return 0; } does not work as expected - last assert failed. With text_iarchive/text_oarchive or binary_iarchive/binary_oarchive everything works fine. With polymorphic_text_archive another assert failed - is.good() returns false. I'm using VC 7.1 compiler. I had trying to compile this code with Intel 8.1 compiler but got errors, identical for polymorphic binary and text archives : Compiling with Intel(R) C++ 8.1 ...(Intel C++ Environment) TestPolyArchives.cpp C:\boost_1_32_0\boost/serialization/binary_object.hpp(43): error #308: function "boost::archive::polymorphic_oarchive::save_binary" is inaccessible ar.save_binary(m_t, m_size); ^ detected during: instantiation of "void boost::serialization::binary_object::save(Archive &, const unsigned int) const [with Archive=boost::archive::polymorphic_oarchive]" at line 90 of "C:\boost_1_32_0\boost/serialization/access.hpp" instantiation of "void boost::serialization::access::member_save(Archive &, const T &, const unsigned int) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 42 of "C:\boost_1_32_0\boost/serialization/split_member.hpp" instantiation of "void boost::serialization::detail::member_saver<Archive, T>::invoke(Archive &, const T &, const unsigned int) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 63 of "C:\boost_1_32_0\boost/serialization/split_member.hpp" instantiation of "void boost::serialization::split_member(Archive &, T &, const unsigned int) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 49 instantiation of "void boost::serialization::binary_object::serialize(Archive &, const unsigned int) [with Archive=boost::archive::polymorphic_oarchive]" at line 106 of "C:\boost_1_32_0\boost/serialization/access.hpp" [ 4 instantiation contexts not shown ] instantiation of "void boost::archive::detail::save_non_pointer_type<Archive, T>::invoke(Archive &, const T &) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 551 of "C:\boost_1_32_0\boost/archive/detail/oserializer.hpp" instantiation of "void boost::archive::save(Archive &, const T &) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 106 of "C:\boost_1_32_0\boost/archive/polymorphic_oarchive.hpp" instantiation of "void boost::archive::polymorphic_oarchive::save_override(const T &, int) [with T=boost::serialization::binary_object]" at line 87 of "C:\boost_1_32_0\boost/archive/detail/interface_oarchive.hpp" instantiation of "Archive &boost::archive::detail::interface_oarchive<Archive>::operator&(const T &) [with Archive=boost::archive::polymorphic_oarchive, T=boost::serialization::binary_object]" at line 159 of "C:\boost_1_32_0\boost/archive/detail/polymorphic_oarchive_impl.hpp" instantiation of "boost::archive::polymorphic_oarchive &boost::archive::detail::polymorphic_oarchive_impl<ArchiveImplementation>::operator&(const T &) [with ArchiveImplementation=boost::archive::binary_oarchive_impl<boost::archive::binary_oarchive>, T=boost::serialization::binary_object]" C:\boost_1_32_0\boost/serialization/binary_object.hpp(47): error #308: function "boost::archive::polymorphic_iarchive::load_binary" is inaccessible ar.load_binary(const_cast<void *>(m_t), m_size); ^ detected during: instantiation of "void boost::serialization::binary_object::load(Archive &, const unsigned int) [with Archive=boost::archive::polymorphic_iarchive]" at line 98 of "C:\boost_1_32_0\boost/serialization/access.hpp" instantiation of "void boost::serialization::access::member_load(Archive &, T &, const unsigned int) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 53 of "C:\boost_1_32_0\boost/serialization/split_member.hpp" instantiation of "void boost::serialization::detail::member_loader<Archive, T>::invoke(Archive &, T &, const unsigned int) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 63 of "C:\boost_1_32_0\boost/serialization/split_member.hpp" instantiation of "void boost::serialization::split_member(Archive &, T &, const unsigned int) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 49 instantiation of "void boost::serialization::binary_object::serialize(Archive &, const unsigned int) [with Archive=boost::archive::polymorphic_iarchive]" at line 106 of "C:\boost_1_32_0\boost/serialization/access.hpp" [ 5 instantiation contexts not shown ] instantiation of "void boost::archive::load(Archive &, T &) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 107 of "C:\boost_1_32_0\boost/archive/polymorphic_iarchive.hpp" instantiation of "void boost::archive::polymorphic_iarchive::load_override(T &, int) [with T=boost::serialization::binary_object]" at line 105 of "C:\boost_1_32_0\boost/archive/detail/interface_iarchive.hpp" instantiation of "Archive &boost::archive::detail::interface_iarchive<Archive>::operator>>(const T &) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 111 of "C:\boost_1_32_0\boost/archive/detail/interface_iarchive.hpp" instantiation of "Archive &boost::archive::detail::interface_iarchive<Archive>::operator&(const T &) [with Archive=boost::archive::polymorphic_iarchive, T=boost::serialization::binary_object]" at line 182 of "C:\boost_1_32_0\boost/archive/detail/polymorphic_iarchive_impl.hpp" instantiation of "boost::archive::polymorphic_iarchive &boost::archive::detail::polymorphic_iarchive_impl<ArchiveImplementation>::operator&(const T &) [with ArchiveImplementation=boost::archive::binary_iarchive_impl<boost::archive::binary_iarchive>, T=boost::serialization::binary_object]" compilation aborted for .\TestPolyArchives.cpp (code 2) With best regards, Sergey.

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compile 1_32 on darwin fails for test library (unit_test, prg_exec_monitor, etc)
by John A Meinel 12 Jan '05

12 Jan '05

I'm currently trying to compile all of boost on OS X (10.3.7), using TOOLS=darwin. I already read about the problems with xml_grammar, so I just added: #ifdef NDEBUG template class basic_xml_grammer<char>; #endif //NDEBUG This at least lets the compilation finish. And I'm not using boost::serialization yet. Hopefully Apple will get a fix (I am compiling with their latest build 1671). But I'm running into another problem during the link stage of the test libraries "libboost_unit_test_framework.dylib" It happens in both debug and release builds, I get: ld: Undefined symbols: init_unit_test_suite(int, char**) I found this function defined in auto_unit_test.hpp, and referenced in some of the .cpp files. Now, I'm guessing that this might be intentionally undefined, so that when you bind to the dynamic library, you define your own initialization (probably through a macro), and the library uses that. Has anyone else had this problem? I tried looking through the regression tests, but I haven't found anything that looks like this problem. I saw this post on the mailing list: http://thread.gmane.org/gmane.comp.lib.boost.user/6489 But there were no follow-ups, so I decided to re-post. Is this just a problem with dynamic libraries on Mac, that they can't have undefined symbols? Or is it something else? If it just means that you can only use the static library, that's fine. But why is it compiling the dynamic ones on Mac if they won't succeed? Thanks, John =:->

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Re: size of libboost_thread-gcc-mt.so
by Vladimir Prus 12 Jan '05

12 Jan '05

Alexander Nasonov wrote: > Amerio wrote: >> Hello, >> After compiling libboost_thread-gcc-mt.so on debian/gcc-2.95.4, this so >> weights 195kB, while libpthread weights only 100kB. >> Why such a huge difference ? Isn't boost::thread meant to be as >> lightweight as possible ? > > Try building it with Boost.Build v2 (bjam --v2 gcc release). It's only > 64K because read_write_mutex.o (223K in release) is excluded from link. > I don't know whether it's intentional or an oversight. I'm afraid it's an oversight -- that's a recently added feature. I'm surprised that it adds so much to the size though, let me try here. Without read_write_mutex the size of gcc/release/shared build is 46K. With read_write_mutex the size is 136K. Wow, that's a difference! When I comment out explicit template instantiations in that source file, the library is becomes 76K. The comment says explicit instantination are needed to detect syntax errors in templates but those instantination bloat the library. BTW, I'm not sure read_write_mutex should be a template, either. Maybe, we need class polymorphic_mutex; and template<class Mutex> class concrete_polymorphic_mutex : public polymorphic_mutex { }; and read_write_mutex_impl must be implemented in terms of polymorphic_mutex? - Volodya

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B is_convertible to A<T> for some T
by Agoston Bejo 12 Jan '05

12 Jan '05

Hello, how do I express through template metaprogramming or in a similar way that a class is convertible to a template class for some T1? I.e., the condition: "There exists some T1 such that B is convertible to A<T1>". An example program: (Platform: VC++7.1) --------------------------------------------------- #include <iostream> #include <boost/utility/enable_if.hpp> using namespace std; using namespace boost; template<typename T> struct A {}; struct B : public A<int> {}; template<typename T> struct isA { static const bool value = false; }; template<typename T> struct isA< A<T> > { static const bool value = true; }; // This would give the desired result, but I don't know how it should // legally be expressed it in C++ (if anyhow): //template<typename T, typename TEnabler = void> //struct A { static const bool value = false; }; // //template<typename T, > //struct isA< T, // enable_if<{{T where T is convertible to A<T1> for some T1}}> > //{ // static const bool value = true; //}; int _tmain(int argc, _TCHAR* argv[]) { cout << isA< A<int> >::value << endl; // 1 cout << isA< A<double> >::value << endl;// 1 cout << isA< B >::value << endl; // 0 - not what I want cout << isA<int>::value << endl; // 0 return 0; } ---------------------------------------------------

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Boost Graph Reading and Writing ATT graphviz example compile error
by Welson Sun 12 Jan '05

12 Jan '05

Hi, My platform is Linux (Fedora Core 2), gcc version: gcc (GCC) 3.3.3 20040412 (Red Hat Linux 3.3.3-7) I need to read and write the ATT graphviz format, so this is what I did: 1. Generated the libbgl-viz library. In boost_1_32_0/libs/graph/src/ directory, use the default Makefile, generated the libbgl-viz library without error. And I copied them to /usr/local/lib 2. g++ boost_1_32_0/libs/graph/example/graphviz.cpp, but I got the nasty error: ccVhyZaG.o(.text+0x602):graphviz.cpp: undefined reference to `boost::read_graphviz(std::basic_string<char, std::char_t raits<char>, std::allocator<char> > const&, boost::subgraph<boost::adjacency_lis t<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_attr ibute_t, std::map<std::basic_string<char, std::char_traits<char>, std::allocator <char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> > , std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::basic_string<char, std::char_traits<char>, s td::allocator<char> > const, std::basic_string<char, std::char_traits<char>, std ::allocator<char> > > > >, boost::no_property>, boost::property<boost::edge_attr ibute_t, std::map<std::basic_string<char, std::char_traits<char>, std::allocator <char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> > , std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::basic_string<char, std::char_traits<char>, s td::allocator<char> > const, std::basic_string<char, std::char_traits<char>, std ::allocator<char> > > > >, boost::property<boost::edge_index_t, int, boost::no_p roperty> >, boost::property<boost::graph_graph_attribute_t, std::map<std::basic_ string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<c har, std::char_traits<char>, std::allocator<char> >, std::less<std::basic_string <char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pai r<std::basic_string<char, std::char_traits<char>, std::allocator<char> > const, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, bo ost::property<boost::graph_vertex_attribute_t, std::map<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::cha r_traits<char>, std::allocator<char> >, std::less<std::basic_string<char, std::c har_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::basic_ string<char, std::char_traits<char>, std::allocator<char> > const, std::basic_st ring<char, std::char_traits<char>, std::allocator<char> > > > >, boost::property <boost::graph_edge_attribute_t, std::map<std::basic_string<char, std::char_trait s<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::less<std::basic_string<char, std::char_traits<char >, std::allocator<char> > >, std::allocator<std::pair<std::basic_string<char, st d::char_traits<char>, std::allocator<char> > const, std::basic_string<char, std: :char_traits<char>, std::allocator<char> > > > >, boost::property<boost::graph_n ame_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, b oost::no_property> > > >, boost::listS> >&)' collect2: ld returned 1 exit status What's the matter?

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