December 2012 - Boost - lists.preview.boost.org

A GUI Library
by jinhao 09 Nov '17

09 Nov '17

Hi, all I am developing a GUI library, it takes aim at easy-to-use and portable library for modern C++ methods. The project at http://stdex.sourceforge.net A git repository at http://nanapro.codeplex.com A brief at http://nanaproject.wordpress.com/2011/12/16/preliminary-study-of-nana-c-lib… Is there any interest in this library? Regards Jinhao

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bad include guards
by Steven Watanabe 26 Jan '17

26 Jan '17

AMDG The following pairs of files have identical include guards ./boost/concept_check/general.hpp ./boost/concept/detail/msvc.hpp ./boost/concept_check/msvc.hpp ./boost/concept/detail/msvc.hpp ./boost/filesystem/cerrno.hpp ./boost/cerrno.hpp ./boost/interprocess/containers/tree.hpp ./boost/interprocess/containers/detail/tree.hpp ./boost/mpl/min_max.hpp ./boost/mpl/max.hpp ./boost/mpl/vector/aux_/front.hpp ./boost/mpl/list/aux_/front.hpp ./boost/multi_index/identity_fwd.hpp ./boost/multi_index/identity.hpp ./boost/python/pointee.hpp ./boost/python/detail/pointee.hpp ./boost/spirit/phoenix/closures.hpp ./boost/lambda/closures.hpp ./boost/xpressive/proto/v1_/proto_typeof.hpp ./boost/xpressive/proto/proto_typeof.hpp ./libs/config/test/boost_no_dep_nested_class.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/config/test/boost_no_mem_templates.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/config/test/boost_no_std_allocator.ipp ./libs/config/test/boost_has_vc6_mem_templ.ipp ./libs/conversion/test.hpp ./libs/any/test.hpp ./libs/interprocess/example/print_container.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/interprocess/test/expand_bwd_test_template.hpp ./libs/interprocess/test/allocation_test_template.hpp ./libs/interprocess/test/printcontainer.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/interprocess/test/print_container.hpp ./libs/interprocess/example/printcontainer.hpp ./libs/iostreams/test/detail/utf8_codecvt_facet.hpp ./boost/detail/utf8_codecvt_facet.hpp ./libs/regex/test/regress/test_regex_search.hpp ./libs/regex/test/regress/test_partial_match.hpp ./libs/serialization/test/C.hpp ./libs/serialization/test/A.hpp ./libs/xpressive/perf/regex_comparison.hpp ./libs/regex/performance/regex_comparison.hpp ./tools/inspect/time_string.hpp ./tools/common/time_string.hpp In Christ, Steven Watanabe

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Arguing about names in Boost libraries
by Edward Diener 06 May '15

06 May '15

What is wrong with the people commenting on libraries for Boost who are so concerned about the names being used ? We are talking only about C++ identifiers and yet there are now endless discussions where people disagree on names or argue that some name is not what they want or that they like some other name, with a list of names that they find adequate. This is irrelevant. There is something mentally wrong about all those peoples spending endless amounts of time around this issue. I notice this does not happen nowadays for just one library but for ever single library, or proposed library, which is mentioned on this mailing list. Is this the way all of you people actually work in your daily jobs, or on your own projects, spending hours and days arguing with others about C++ identifiers for every little thing ? Are you not aware of the absurdity of your endless remarks ? Grow up ! Surely there are better things to do than carry on endlessly about some name, that is should be x or y or z or some other inane preferable list. It's time for somebody to say this, so I will do it. A C++ identifier name, as long as it is vaguely about what the functionality entails, is perfectly adequate. It does not have to satisfy everyone in the universe. Period !

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IDE for developing Boost
by Jens Müller 20 Dec '14

20 Dec '14

Hi, I am looking for recommendations for developing Boost, especially code in the graph library. At work, most developers (not for Boost, for some commercial software), most developers are using Eclipse. This works quite fine as soon as it has properly auto-discovered include paths etc. But before fiddling around with Eclipse to get all the settings right, I'd wanted to to ask for your recommendations. And maybe there are already settings available to make it "just work", at least initially. Cheers, Jens

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Why no non-null smart pointers?
by Ross MacGregor 29 Apr '14

29 Apr '14

I just created a very small smart pointer libary for our project. It will contain two types of shared pointers: SharedHandle and NullableSharedHandle. SharedHandle will be a shared pointer that cannot be null by ensuring a non-null construction while NullableSharedHandle will basically be a typedef for boost::shared_ptr. I firmly believe that code can be made more reliable by minimizing the use of nullable pointers. To this end, I think it is important that we start using non-null pointer types. Ideally the compiler would be able to understand a non-null pointer and catch bugs at compile time, but I think we can still improve things with a few runtime checks. If we make sure that a shared pointer is constructed with a non-null pointer and ban any reset() type methods, we guarentee that it points to something. This can be beneficial for the following reasons: 1. Any function that uses this type will no longer be burdened with precondition checks to make sure variables of this type are not null. 2. It's type is simply more explicit and better explains its function. 3. Moving the non-null check to the creation phase will reduce the possibility of encountering null pointer exceptions at runtime (assuming there are many more pointer references than constructor calls). So my little pointer library seems to make a lot of sense, but if so why hasn't this simple smart pointer variation made it into boost yet? Has this been discussed somewhere already? My search on non-null smart pointers is not revealing much discussion on the topic. Regards, Ross

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Interest in Base2/16/32/64 Encoding Library?
by Thomas Kemmer 27 Jan '14

27 Jan '14

Dear Boost Developers, I would like to know if there is interest in incorporating a generic Base2/16/32/64 encoding library into Boost. I am the author of such a libray, hosted at http://code.google.com/p/stlencoders/ and would be willing to contribute and make the effort of "Boostifying" it, if the Boost community is interested in such a thing. There have been several suggestions for a Base64 encoding library on this mailing list in the past. Most of them have been dismissed, since Boost already provides a Base64 implementation with Boost.Serialization's "Dataflow Iterators". Though I appreciate the dataflow iterator's design, from personal experience I think that for the basic task of encoding/decoding, a higher-level interface, e.g. one that takes padding and intermittent whitespace (MIME) into account, would benefit many developers. Currently, the stlencoders library - implements the Base16, Base32 and Base64 encoding schemes as defined in RFC 4648. Base2, i.e. binary encoding, is also supported. - implements encoding and decoding operations as generic algorithms that operate on STL-style iterators - supports different encoding alphabets using custom traits classes - supports different character types - lets the user define if/which non-alphabet characters should be ignored via predicates - provides reasonable performance that matches most "plain C" implementations stlencoders is currently designed as a stand-alone library with no dependencies on Boost (or anything but C++03); it would therefore take some effort and guidance from the community to properly integrate it with the rest of Boost. I would therefore appreciate any feedback regarding your interest in this. Kind Regards, Thomas

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[mpl] integral_c [type_traits] integral_constant limits
by vicente.botet 21 Oct '13

21 Oct '13

Hi, I was testing Boost.Ratio with gcc-4.6 c++0x and I get some compile errors when instantiating std::cout << boost::mpl::integral_c< boost::intmax_t, boost::integer_traits<boost::intmax_t>::const_max >::value ; ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp: In instantiation of 'mpl_::integral_c<long long int, 0x7fffffffffffffffll>': ratio_io\ratio_io.pass.cpp:24:6: instantiated from here ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp:72:96: warning: integer overflow in expression [-Woverflow] ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp:72:96: error: '-0x8000000000000000ll' is not a valid template argument for type 'long long int' because it is a non-constant expression ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp:72:96: error: '-0x8000000000000000ll' is not a constant expression integral_wrapper.hpp:72 contains typedef AUX_WRAPPER_INST( BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (value + 1)) ) next; The same line pass with gcc-4.6, gcc-4.5 and gcc-4.5 c++0x with just a warning. ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp: In instantiation of 'mpl_::integral_c<long long int, 0x7fffffffffffffffll>': ratio_io\ratio_io.pass.cpp:23:6: instantiated from here ..\..\..\../boost/mpl/aux_/integral_wrapper.hpp:72:96: warning: integer overflow in expression [-Woverflow] integral_c is by integral_constant, but integral_constant doesn't needs next a prior types. This means that with the current implementation we can not use integral_constant with the max value of the type. Do you think this is a bug in integral_constant? Best, _____________________ Vicente Juan Botet Escribá http://viboes.blogspot.com/

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[scope_exit] D-style scope(failure) and scope(success) in C++
by Evgeny Panasyuk 30 Sep '13

30 Sep '13

Hello all, D language has scope(exit), scope(success) and scope(failure) features - http://dlang.org/statement.html#ScopeGuardStatement : "... scope(exit) executes NonEmptyOrScopeBlockStatement when the scope exits normally or when it exits due to exception unwinding. scope(failure) executes NonEmptyOrScopeBlockStatement when the scope exits due to exception unwinding. scope(success) executes NonEmptyOrScopeBlockStatement when the scope exits normally. ..." Andrei Alexandrescu describes some of uses cases for scope(exit), scope(success), scope(failure) at his recent talk : http://channel9.msdn.com/Events/Lang-NEXT/Lang-NEXT-2012/Three-Unlikely-Suc… There is Boost.ScopeExit library which emulates D's scope(exit) via BOOST_SCOPE_EXIT macro, but there are no analogues for D's scope(failure) and scope(success). Current alternative for these features is ScopeGuard idiom ( http://en.wikibooks.org/wiki/More_C%2B%2B_Idioms/Scope_Guard , http://www.drdobbs.com/cpp/generic-change-the-way-you-write-excepti/1844037… ). Boost.ScopeExit library itself suggests to use ScopeGuard - http://www.boost.org/doc/libs/1_51_0/libs/scope_exit/doc/html/scope_exit/al… : " Boost.ScopeExit is similar to scope(exit) feature built into the D programming language. A curious reader may notice that the library does not implement scope(success) and scope(failure) of the D language. Unfortunately, these are not possible in C++ because failure or success conditions cannot be determined by calling std::uncaught_exception (see Guru of the Week #47 for details about std::uncaught_exception and if it has any good use at all). However, this is not a big problem because these two D's constructs can be expressed in terms of scope(exit) and a bool commit variable (similarly to some examples presented in the Tutorial section). " I have made small library ( https://github.com/panaseleus/stack_unwinding#d-style-scope-guardsactions ) which supplies primitives (class unwinding_indicator, UNWINDING_AWARE_DESTRUCTOR macro) to determining when object destructor is called due to stack-unwinding or due to normal scope leaving. Currently it is implemented on top of platform-specific implementation of uncaught_exception_count function and tested on: {MSVC2005, MSVC2008, MSVC2010, MSVC2012, GCC4.1.2, GCC4.4.6, Clang3.2}x{x32, x64}x{default settings}. uncaught_exception_count is a function similar to std::uncaught_exception from standard library, but instead of boolean result it returns unsigned int showing current count of uncaught exceptions. Such primitives allow us to implement scope(success) and scope(failure) features in C++. I have made several proof-of-concepts: * https://github.com/panaseleus/stack_unwinding/blob/master/examples/scope_ac… * https://github.com/panaseleus/stack_unwinding/blob/master/examples/example_… * https://github.com/panaseleus/stack_unwinding/blob/master/examples/scope_gu… * https://github.com/panaseleus/stack_unwinding/blob/master/examples/boost_sc… boost_scopes.cpp example shows usage of BOOST_SCOPE_FAILURE and BOOST_SCOPE_SUCCESS: try { cout << "Case #1: stack unwinding" << endl; BOOST_SCOPE_EXIT(void) { cout << "exit" << endl; } BOOST_SCOPE_EXIT_END BOOST_SCOPE_FAILURE(void) { cout << "failure" << endl; } BOOST_SCOPE_FAILURE_END BOOST_SCOPE_SUCCESS(void) { cout << "success" << endl; } BOOST_SCOPE_SUCCESS_END throw 1; } catch(int){} { cout << "Case #2: normal exit" << endl; BOOST_SCOPE_EXIT(void) { cout << "exit" << endl; } BOOST_SCOPE_EXIT_END BOOST_SCOPE_FAILURE(void) { cout << "failure" << endl; } BOOST_SCOPE_FAILURE_END BOOST_SCOPE_SUCCESS(void) { cout << "success" << endl; } BOOST_SCOPE_SUCCESS_END } Output is: " Case #1: stack unwinding failure exit Case #2: normal exit success exit " Currently BOOST_SCOPE_FAILURE and BOOST_SCOPE_SUCCESS are implemented based on boost_1_51_0/boost/scope_exit.hpp by copy-paste and replace (just for proof-or-concept, of course it is possible solution with much less duplication). Semantically meaningful changes can be viewed as diff at https://github.com/panaseleus/stack_unwinding/commit/d5513404323490ea99d9b6… Before posting here, I made posts on several C++ forums, but unfortunately get only a few feedbacks regarding ScopeFailure and ScopeSuccess. What do you think? Thank you. P.S. Related discussion: http://lists.boost.org/Archives/boost/2010/09/171051.php Best Regards, Evgeny Panasyuk

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[asio] Randomly having problems reading from the socket
by Torben Wiggerich 29 Jul '13

29 Jul '13

Hi all, I have some problems using the boost.asio.read for a TCP-socket. So far it works fine, but it randomly stops the transfer for at least 5 seconds. To resolve the error I used a simple synchronous server and client from the boost examples and modified it too send a larger amount of data. (307400 Bytes; this size comes from the program I'm trying to get run). On the client side I also changed the reading from the socket to read the complete data with boost.asio.read and transfer_all as argument. Both, server and client, measure the time for sending and reading to the socket and will give an error if it needs more than 1 second. Here is the sourcecode for the server: #include <iostream> #include <string> #include <boost/asio.hpp> #include <boost/date_time/posix_time/posix_time.hpp> using boost::asio::ip::tcp; using namespace boost::posix_time; int main() { try { boost::asio::io_service io_service; tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), 8002)); tcp::socket socket(io_service); acceptor.accept(socket); unsigned char * array = new unsigned char[307400]; for (;;) { boost::system::error_code ignored_error; ptime startTime = microsec_clock::universal_time(); boost::asio::write(socket, boost::asio::buffer( array, 307400 ), boost::asio::transfer_all(), ignored_error); time_duration neededTime = microsec_clock::universal_time() - startTime; if ( neededTime.total_milliseconds() > 1000 ) { std::cout << "ERROR needed too much time: " << neededTime.total_milliseconds() << "ms" << std::endl; } } } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } My client sourcecode: #include <iostream> #include <boost/array.hpp> #include <boost/asio.hpp> #include <boost/date_time/posix_time/posix_time.hpp> using boost::asio::ip::tcp; using namespace boost::posix_time; int main(int argc, char* argv[]) { try { if (argc != 2) { std::cerr << "Usage: client <host>" << std::endl; return 1; } boost::asio::io_service io_service; boost::asio::ip::tcp::endpoint endpoint( boost::asio::ip::address::from_string( argv[1] ), 8002 ); tcp::socket socket(io_service); boost::system::error_code error = boost::asio::error::host_not_found; socket.connect( endpoint, error ); if (error) throw boost::system::system_error(error); int counter = 0; unsigned char* array = new unsigned char[307400]; for (;;) { boost::system::error_code error; ptime startTime = microsec_clock::universal_time(); size_t len = boost::asio::read( socket, boost::asio::buffer( array, 307400 ), boost::asio::transfer_all(), error ); time_duration neededTime = microsec_clock::universal_time() - startTime; if ( error ) { printf( "body read error %s\n", error.message().c_str() ); } if ( counter % 5000 == 0 ) { std::cout << "passed: " << counter << "\r"; } ++counter; if ( neededTime.total_milliseconds() > 1000 ) { std::cout << "ERROR needed too much time: " << neededTime.total_milliseconds() << "ms" << std::endl; } } } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } To reproduce the error just let it run for a while. It can take up to 30 minutes or even more... After a while it will produce the line: "ERROR needed too much time: 5007ms". Maybe with slightly different times, but all around 5 seconds. I tested it on different machines with Windows Vista and Seven. So am I'm doing sth. wrong? Is the reading from the socket correct? I'm using boost version 1.44. Kind regards Torben Wiggerich

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A more convenient Variant visitation syntax
by Kevin Wu Won 19 Jul '13

19 Jul '13

While Boost Variant is a wonderful library that fills a genuine hole in the C++ language, it is not as nice to use as it could be. The "correct" way to unwrap a variant is to apply a static visitor, but this method carries a high syntactic burden because it needs the user to define a class (probably somewhere far away) just so they can "switch" on the type of the object stored in the variant. I came up with a solution where the handler functions can be specified inline with C++11 lambdas. Here's an example: boost::variant< int, std::string > u("hello world"); int result = match(u, [](int i) -> int { return i; }, [](const std::string & str) -> int { return str.length(); }); The `match` function accepts the variant followed by the handler functions. The functions can be specified in any order. It will fail to compile if the functions do not match the types of the variant, if the return types are not all the same, or if a non-unary function is supplied. This is C++11 only because it's quite pointless without lambda functions. I've tested it with gcc 4.7. It doesn't work on gcc 4.6, which can't handle the variadic templates. Here's the code: https://github.com/exclipy/inline_variant_visitor What do you think? This started out for me as an exercise to learn template metaprogramming and C++11, but hopefully, it can actually evolve into something useful.

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De Bruijn Bind (alternate bind syntax) Interest?
by David Sankel 24 Jun '13

24 Jun '13

Hello all, I've been working on an alternate bind syntax based on De Bruijn indices[1]. The syntax is very simple, yet the terms are very powerful. Here is an example of a function const that takes in an argument c and returns another function that, for all input, returns c: //λx.λy.x = λλ1 with De Bruijn indices. auto const_ = abs<1>( abs<1>( var<1,0>() ) ); More examples, further explanation, and an implementation are available here[2]. I'm thinking that this library could also be useful as a core for more syntax heavy bind variations. David [1] http://en.wikipedia.org/wiki/De_Bruijn_index [2] http://bitbucket.org/camior/de-bruijn-bind/ -- David Sankel Sankel Software www.sankelsoftware.com 585 617 4748 (Office)

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[TypeErasure] references
by Chapman, Alec 10 May '13

10 May '13

Hi Steven, I have a somewhat-generic type erasure class that I would like to switch to yours. The main difficulty I can see is in the way capturing by reference is handled. The approach I take in my class is to pass a boost::reference_wrapper to the constructor: typedef mpl::vector<copy_constructible<>, type_id_<>, incrementable<> > requirements; int i = 0; any<requirements> x(boost::ref(i)); // capture i by reference ++x; // i == 1 any<requirements> y(x); // makes a copy of i ++y; // i == 1, any_cast<int>(y) == 2 My motivation is that I have a bunch of template functions already written that I often call directly, but in other cases I need to compile them separately by instantiating them with any<...>: ---------------------- module 1 ------------------------- // some long algorithm that I don't want to modify to be aware of any<...> template<class T> void f(T& t) { ++t; T t2 = t; ++t2; // do something with t2 } // make a type-erased version for separate compilation void any_f(any<requirements>& x) { return f(x); } -------------------- module 2 ---------------------------- // provide a thin wrapper that applies type erasure before calling any_f template<class T> void f_fwd(T& t) { any<requirements> x(boost::ref(t)); any_f(x); } // some function that needs to call f void g(int& i) { // do something with i... // then pass it to f f_fwd(i); } Is something like this possible with your method? Are there advantages that I'm not seeing to having the type signature contain information about whether the object is held by reference? Thanks, Alec

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What Should we do About Boost.Test?
by Dave Abrahams 16 Apr '13

16 Apr '13

Hi All, I was just going through Boost.Test to try to figure out how to teach it, and while it looks to have substantial value, it is also in quite a mess. It contains loads of features that are exercised in the examples/ directory but neither included in any of the tests nor documented. There are facilities for command-line argument parsing! There are "decorators" that turn on/off features for test cases. There is support for mock objects! These are cool and sometimes necessary features, but who knew? The third tutorial page (http://www.boost.org/doc/libs/1_51_0/libs/test/doc/html/tutorials/new-year-…) has a glaring typo in the code examples: "BOOST_AUTO_EST_CASE". There's no reference manual at all. There are nearly-identical files in the examples/ directory called "est_example1.cpp" and "test_example1.cpp" (Did the "t" key on someone's keyboard break?) I could go on, but where would I stop? I don't know what to do about this. Because of the lack of redundancy (i.e. tests and documentation), it's hard to tell whether this library is correct or even to define what "correct" should mean. It seems like, as long as the code is incompletely / incorrectly documented and tested, it's just someone's personal coding project that we happen to keep shipping with Boost, and not really a library for general use. This situation reflects poorly on Boost as a whole and the fact that it centers around a _testing_ library, which is concerned with robustness... well, let's just say that the irony isn't lost on me. I don't mean this posting as an attack on Gennadiy in any way, but I think the situation is unacceptable and therefore am opening a discussion about what should happen. As a straw man, I'll make this suggestion: - Boost.Test is officially deprecated in the next release - Its documentation, such as it is, is removed from the release after that - Meanwhile, other tests in Boost that use this library are rewritten to use a different mechanism - The code is removed from Boost thereafter I am not at all attached to removing Boost.Test from Boost, but IMO rescuing it would require a significant new investment of time and energy from people who are committed to bringing the library up to par with the rest of what we do. (I seriously thought about volunteering for this myself, but realistically speaking, I don't have the time, and volunteering for something you can't actually do is worse than not volunteering at all.) Even if volunteers show up, I'd suggest proceeding with the plan above, subject to reversal at any time the work actually gets done. Thoughts? -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost

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[fusion] What do we do with nil ?
by Joel de Guzman 31 Mar '13

31 Mar '13

Hello, This is a constantly nagging issue. There are a couple of places where nil is a PP define especially on the Mac: - objc.h #ifndef nil #define nil __DARWIN_NULL #endif and - MacTypes.h #ifndef nil #define nil NULL #endif So people complain because fusion uses nil as: namespace boost { namespace fusion { struct nil; }} So, nil is a reserved word in Objective-C. But this is C++! And that define is SUCH A BAD PRACTICE in C++! Some folks, like Paul Mensonides maintains a strong stance against this: I would just use #define nil nil as a sanity check and call it done. If the symbol is already defined, compilation error (or at least warning on overly permissive compilers). The symbol will be need to be undefined in between the inclusion of the two libraries. Workarounds like nil_ and (min)(...) just perpetuate the problem. Fix the root problem rather than treating the symptom indefinitely. Otherwise, where is the line drawn? Even if you can't provide a transparent fix (such as defining nil as a constant and min/max as functions), the backwards compatibility argument fails in the long run. The amount of effort required to make the necessary changes to existing code will eventually be outweighed by the effort to implement workarounds put into new code (as well as educate everyone that they are necessary)--especially in cases like these which can mostly be emulated in a way that causes most existing code to work. As I said over and over again, I'm listening and I would want to "fix" this issue if someone comes up with a reasonable (tested) patch that: 1) Detects the platform 2) Renames fusion::nil to something else (only for the affected platform) Yet, no-one wants to do this. Instead we get nasty remarks such as those found here: https://svn.boost.org/trac/boost/ticket/5010#comment:16 What do we do? I'm seeking for a resolution. Regards, -- Joel de Guzman http://www.boostpro.com http://boost-spirit.com

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[config] consexpr workaround
by vicente.botet 21 Mar '13

21 Mar '13

Hi, in order to make easier the introduction of constexpr in a portable way I would like we add a Boost Config workarround. We can define some macros depending on whether BOOST_NO_CONSTEXPR is defined or not. #if defined(BOOST_NO_CONSTEXPR) #define BOOST_CONSTEXPR #define BOOST_CONSTEXPR_OR_CONST const #else #define BOOST_CONSTEXPR constexpr #define BOOST_CONSTEXPR_OR_CONST constexpr #endif For most of the constexpr functions or constructors BOOST_CONSTEXPR will work. constexpr tuple(); =versus= BOOST_CONSTEXPR tuple(); When used for static constants BOOST_CONSTEXPR_OR_CONST is needed as we need to preserv the const keyword when consexpr is not available. static constexpr UIntType xor_mask = a; =versus= static BOOST_CONSTEXPR_OR_CONST UIntType xor_mask = a; We could also add a STATIC_CONSTEXPR macro #define BOOST_STATIC_CONSTEXPR static BOOST_CONSTEXPR_OR_CONST static constexpr UIntType xor_mask = a; =versus= BOOST_STATIC_CONSTEXPR UIntType xor_mask = a; For this case the existing macro BOOST_STATIC_CONSTANT could be modified to use BOOST_CONSTEXPR_OR_CONST when static const was used. static constexpr UIntType xor_mask = a; =versus= BOOST_STATIC_CONSTANT(UIntType, xor_mask = a); Can we introduce this workaround? Best regards, Vicente _____________________ Vicente Juan Botet Escribá http://viboes.blogspot.com/

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[thread] thread_specific_ptr leaks on VS2012 when using std::async()
by Klaim - Joël Lamotte 05 Mar '13

05 Mar '13

Hi, The title says it all. I think I found a memory leak with the help of boost.log author Andrei Semashev. I was using Boost.Log in Visual Studio 2012 (released one) and tried to use Visual Leak Detector because Visual Studio basic leak detector was reporting leaks. I isolated the leaks to usage of log and switched to VLD to check if the basic detector wasn't giving me false positive. I contacted Andrei to see if he could check it but he don't have VS2012 available so I setup some tests to isolate the problem. In the end of our exchange we concluded it was a false positive (it only leak on end of program). However it is still an annoying noise in the leak report logs, so people not understanding the source of this problem might be interested in this email. I attach the whole email exchange to this email, tell me if leak logs are necessary too. The last version of my test is at the end of the email (first program). Basically, the leak appear only when using std::async() in combination of boost::thread_specific_ptr : - using exclusively boost threading libraries (both with dynamic and static linking) result in no leak - using exclusively std threading libraries but not std::async() result in no leak - using std::async() result in a leak The second test program shows that using Intel Threading Building Blocks, I get leaks only if : - I use std::async() in combination with boost::thread_specific_ptr, as before (I mean I use tbb without a leak, then I add a std::async() call to the same task function and there is a leak) - I don't use std::async() but I don't manage the lifetime of tbb task scheduler We think the threads spawned by both tbb (that is supposed to be a superset of ppl) and std::async() (that is supposed to use ppl/concrt task scheduler) are not ended yet when the program reach the end of main (which seems logical as the task scheduler is then managed as a static global), making boost::thread_specific_ptr not release some data on thread destruction, as it is notified too late and any leak detection tool willl generate noise due to this. A way to fix this is to explicitely end the task scheduler, being tbb or ppl/concrt. I will use tbb task scheduler explicitely initialized/terminated in my project so it will solve the problem on my side. Joel Lamotte ------------------------------------ // this program was used to see the memory leak #define TEST_ASYNC // comment this to make it linear and not leak //#define WITH_BOOST_THREADS #define WITH_STD_ASYNC // uncomment this to leak //#define WITH_BOOST_LOG // boost log also leak if std::async is used #include <boost/thread.hpp> #ifdef WITH_BOOST_THREADS # include <boost/thread/future.hpp> # include <boost/chrono.hpp> # define THIS_THREAD boost::this_thread # define THREAD_LIB boost::thread # define CHRONO_LIB boost::chrono # define MY_FUTURE boost::future #else # include <future> # include <thread> # include <chrono> # define THIS_THREAD std::this_thread # define THREAD_LIB std::thread # define CHRONO_LIB std::chrono # define MY_FUTURE std::future #endif #ifdef WITH_BOOST_LOG # include <boost/log/trivial.hpp> # define MY_LOG BOOST_LOG_TRIVIAL(info) #else # include <iostream> # define MY_LOG std::cout << '\n' #endif #define BASIC_VS_LEAK_DETECTOR 0 #define VISUAL_LEAK_DETECTOR 1 #define LEAK_DETECTOR VISUAL_LEAK_DETECTOR #if LEAK_DETECTOR == BASIC_VS_LEAK_DETECTOR # define _CRTDBG_MAP_ALLOC # include <stdlib.h> # include <crtdbg.h> #else # include "vld.h" #endif struct my_data { char data[1024]; my_data() { MY_LOG << "CONSTRUCTOR my_data - " << THIS_THREAD::get_id(); } ~my_data() { MY_LOG << "DESTRUCTOR my_data - " << THIS_THREAD::get_id(); } }; boost::thread_specific_ptr< my_data > ts_ptr; void my_thread_foo() { ts_ptr.reset(new my_data()); } int work() { for( int i = 0; i < 42; ++i ) { MY_LOG << "THIS IS A MESSAGE - I = " << i; MY_LOG << "ts_ptr = " << ts_ptr.get(); my_thread_foo(); THIS_THREAD::sleep_for( CHRONO_LIB::milliseconds(10) ); } return 0; } int main(int argc, char *argv[]) { #if LEAK_DETECTOR == BASIC_VS_LEAK_DETECTOR // First simple memory leak detection for Visual Studio // use _crtBreakAlloc to put a breakpoint on the provided memory leak id allocation //_crtBreakAlloc = 1149; _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ); #endif //int* k = new int[42]; // to check that memory leak detection does work MY_LOG << "Hello, World!"; #ifdef TEST_ASYNC # ifndef WITH_BOOST_THREADS std::vector< std::future<int> > work_in_progress(2); # ifdef WITH_STD_ASYNC for( auto& ftr : work_in_progress ) { ftr = std::async( work ); } # else for( auto& ftr : work_in_progress ) { std::packaged_task< int() > task(work); ftr = task.get_future(); std::thread thread( std::move(task) ); thread.detach(); } # endif for( auto& ftr : work_in_progress ) { ftr.get(); } # else std::vector< boost::unique_future<int> > work_in_progress(42); for( auto& ftr : work_in_progress ) { boost::packaged_task<int> task(work); // boost's packaged_task don't take the full signature as parameter, it takes the return type only ftr = task.get_future(); boost::thread thread( boost::move(task) ); thread.detach(); } for( auto& ftr : work_in_progress ) { ftr.get(); } # endif #else for( int i = 0; i < 42; ++i ) { work(); } #endif MY_LOG << "END"; return EXIT_SUCCESS; } -------------------------------------- // this program tests if the memory leaks appear with Threading Building Blocks #define BASIC_VS_LEAK_DETECTOR 0 #define VISUAL_LEAK_DETECTOR 1 #define LEAK_DETECTOR VISUAL_LEAK_DETECTOR #define WITH_ROOT_TASK //#define WITH_BOOST_LOG //#define WITH_STD_ASYNC // uncomment to leak #ifdef WITH_STD_ASYNC # include <future> #endif #include <thread> #include <atomic> #include <boost/thread.hpp> #include <tbb/tbb.h> #include <tbb/task_scheduler_init.h> #ifdef WITH_BOOST_LOG # include <boost/log/trivial.hpp> # define MY_LOG BOOST_LOG_TRIVIAL(info) #else # include <iostream> # define MY_LOG std::cout << '\n' #endif #if LEAK_DETECTOR == BASIC_VS_LEAK_DETECTOR # define _CRTDBG_MAP_ALLOC # include <stdlib.h> # include <crtdbg.h> #else # include "vld.h" #endif namespace test { struct my_data { char data[1024]; }; boost::thread_specific_ptr< my_data > ts_ptr; void my_thread_foo() { ts_ptr.reset(new my_data()); } class UpdateTask : public tbb::task { public: UpdateTask() : idx( s_idx++ ) { MY_LOG << "[UpdateTask " << idx << " ] " << std::endl; } ~UpdateTask() { MY_LOG << "[/UpdateTask " << idx << " ]" << std::endl; } tbb::task* execute() { MY_LOG << "[" << std::this_thread::get_id() << "] Tick "<< m_count <<std::endl; my_thread_foo(); ++m_count; if( m_count < 100 ) { // make sure this is re-executed this->increment_ref_count(); this->recycle_as_safe_continuation(); } return nullptr; } private: static std::atomic<int> s_idx; std::atomic<int> m_count; const int idx; }; std::atomic<int> UpdateTask::s_idx = 0; class TaskScheduler // using TBB { public: #ifdef WITH_ROOT_TASK TaskScheduler() : m_root_task( *new (tbb::task::allocate_root()) tbb::empty_task ) { m_root_task.increment_ref_count(); } ~TaskScheduler() { m_root_task.destroy(m_root_task); } #endif void register_update_task() { #ifdef WITH_ROOT_TASK m_root_task.increment_ref_count(); UpdateTask& updater = *new(m_root_task.allocate_child()) UpdateTask(); #else UpdateTask& updater = *new(tbb::task::allocate_root()) UpdateTask(); #endif m_task_list.push_back( updater ); } void run_and_wait() { #ifdef WITH_ROOT_TASK m_root_task.spawn( m_task_list ); m_root_task.wait_for_all(); #else tbb::task::spawn_root_and_wait( m_task_list ); #endif } private: tbb::task_list m_task_list; // uncomment the following line to not leak tbb //tbb::task_scheduler_init m_engine_instance; // We explicitly create and destroy the TBB task scheduler to avoid memory leak warning noises. #ifdef WITH_ROOT_TASK tbb::task& m_root_task; #endif }; void tbb_test() { TaskScheduler task_scheduler; for( int i = 0; i < 50; ++i ) { task_scheduler.register_update_task(); } task_scheduler.run_and_wait(); } } int main(int argc, char *argv[]) { #if LEAK_DETECTOR == BASIC_VS_LEAK_DETECTOR // First simple memory leak detection for Visual Studio // use _crtBreakAlloc to put a breakpoint on the provided memory leak id allocation //_crtBreakAlloc = 148; _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ); #endif #ifdef WITH_STD_ASYNC std::atomic<bool> finished = false; std::async( [&]{ while( !finished ) { MY_LOG << "POP"; test::my_thread_foo(); std::this_thread::sleep_for( std::chrono::milliseconds(500) ); } } ); #endif test::tbb_test(); #ifdef WITH_STD_ASYNC finished = true; #endif MY_LOG << "\nEND"; std::this_thread::sleep_for( std::chrono::seconds(4) ); return 0; }

3 5

[thread] boost::thread and thread safety annotations
by Wladimir 04 Mar '13

04 Mar '13

Hello, The Clang C++ compiler project is currently working on a thread safety analyzer. By making use of so-called thread safety annotations within the source code, several problems with synchronization primitives can be found statically. For example: usage of a data structure without acquiring its guarding lock. See here for an overview of the available attributes: http://clang.llvm.org/docs/LanguageExtensions.html#threadsafety It is customary to use these attributes by defining macros, for compatibility: http://www.mail-archive.com/linuxkernelnewbies@googlegroups.com/msg01455.ht… At one time, it was also supposed to end up in G++, but this was abandoned in favor of clang (see http://gcc.gnu.org/wiki/ThreadSafetyAnnotation) But at least the annotations are fairly standardized. I think it would be useful to add these annotations to boost::thread, so that projects using that library can make use of the static checking. As I understand it, is only a matter of marking data structures that serve as lock/scoped_lock (such as boost::mutex, boost::recursive_mutex, ...), and methods that act upon the lock with the appropriate attributes. Any interest in this? Regards, Wladimir

2 1

Fwd: [Thread] Solution to conflict with MFC?
by Thorsten Ottosen 28 Feb '13

28 Feb '13

Hi Thread maintainers, Anthony speaks about a patch to make this work. Does anyone know where it is? And could it be applied? Thanks -Thorsten -------- Original Meddelelse -------- Subject: [Thread] Solution to conflict with MFC? Date: Tue, 26 Apr 2011 13:28:56 +0200 From: Christian Larsen <contact(a)dword.dk> Reply-To: boost-users(a)lists.boost.org To: boost-users(a)lists.boost.org Newsgroups: gmane.comp.lib.boost.user Hello, I know this has been asked before, but I could not find a good solution. I'm experiencing problems with an application using both MFC and Boost.Thread. Specifically the assertion ASSERT(AfxGetModuleState() != AfxGetAppModuleState()); in AfxCoreInitModule() fails. I link Boost.Thread statically into a DLL in my project. From previous posts to this list and elsewhere, e.g. http://lists.boost.org/boost-users/2009/04/46929.php, I see that the issue is caused by setting _pRawDllMain in tss_pe.cpp. Commenting this line does "solve" the problem, but I would rather not have to hack the Boost source code this way. It seems there is a patch somewhere for this problem (referred to in http://lists.boost.org/boost-users/2009/04/47015.php) but it appears it never made it into the source. Is there any chance of this issue being solved in a better way? Best regards, Christian Larsen

5 9

[Config] N3276 decltype support on VC++ 11
by Michel Morin 28 Feb '13

28 Feb '13

IIRC, Stephan said that VC++ 11 supports N3276 decltype. Shall we "undef" BOOST_NO_CXX11_DECLTYPE_N3276 for VC++ 11? This enables automatic use of decltype-based `boost::result_of`. Trivial patch attached. Regards, Michel

11 79

[multi_index] Move Semantics
by Mark Snelling 27 Feb '13

27 Feb '13

Hi, I've been a user of Boost.MultiIndex for a number of years and think it's a great library. Is there any firm plan to add move semantics? It's been noted under "Future Work" in the docs since Boost 1.32. Regards, Mark

6 10

Problems with building quickbook docs
by Andrey Semashev 21 Feb '13

21 Feb '13

Hi, I'm having problems with building quickbook docs for my library. I have the using quickbook ; as well as doxygen, xsltproc and boostbook in my ~/user-config.jam. When I run: bjam -j 2 release link=static libs/log/doc I get the following error: .../boost-release/tools/build/v2/build/generators.jam:978: in try-one-generator-really *** argument error * rule object(generator)(a)60.run ( project name ? : property-set : sources + ) * called with: ( object(project-target)@1010 filters_reference-xml : object(property-set)@1387 : ) * missing argument sources .../boost-release/tools/build/v2/build/generators.jam:370:see definition of rule 'object(generator)(a)60.run' being called .../boost-release/tools/build/v2/build/generators.jam:1040: in try-one-generator .../boost-release/tools/build/v2/build/generators.jam:1254: in construct-really .../boost-release/tools/build/v2/build/generators.jam:1338: in generators.construct .../boost-release/tools/build/v2/build/targets.jam:1495: in construct .../boost-release/tools/build/v2/build/targets.jam:1298: in object(typed-target)(a)1058.generate .../boost-release/tools/build/v2/build/targets.jam:732: in generate-really .../boost-release/tools/build/v2/build/targets.jam:704: in object(main-target)(a)1164.generate .../boost-release/tools/build/v2/build/targets.jam:848: in targets.generate-from-reference .../boost-release/tools/build/v2/build/targets.jam:1217: in generate-dependencies .../boost-release/tools/build/v2/build/targets.jam:1269: in object(typed-target)(a)1061.generate .../boost-release/tools/build/v2/build/targets.jam:732: in generate-really .../boost-release/tools/build/v2/build/targets.jam:704: in object(main-target)(a)1165.generate .../boost-release/tools/build/v2/build/targets.jam:848: in targets.generate-from-reference .../boost-release/tools/build/v2/build/targets.jam:1217: in generate-dependencies .../boost-release/tools/build/v2/build/targets.jam:1269: in object(typed-target)(a)1062.generate .../boost-release/tools/build/v2/build/targets.jam:732: in generate-really .../boost-release/tools/build/v2/build/targets.jam:704: in object(main-target)(a)1166.generate .../boost-release/tools/build/v2/build/targets.jam:848: in targets.generate-from-reference .../boost-release/tools/build/v2/build/targets.jam:1217: in generate-dependencies .../boost-release/tools/build/v2/build/targets.jam:1269: in object(install-target-class)(a)1065.generate .../boost-release/tools/build/v2/build/targets.jam:732: in generate-really .../boost-release/tools/build/v2/build/targets.jam:704: in object(main-target)(a)1167.generate .../boost-release/tools/build/v2/build/targets.jam:848: in targets.generate-from-reference .../boost-release/tools/build/v2/build/targets.jam:1217: in generate-dependencies .../boost-release/tools/build/v2/build/targets.jam:1399: in basic-target.compute-usage-requirements .../boost-release/tools/build/v2/build/alias.jam:47: in compute-usage-requirements .../boost-release/tools/build/v2/build/targets.jam:1319: in object(alias-target-class)(a)1068.generate .../boost-release/tools/build/v2/build/targets.jam:732: in generate-really .../boost-release/tools/build/v2/build/targets.jam:704: in object(main-target)(a)1168.generate .../boost-release/tools/build/v2/build/targets.jam:258: in object(project-target)(a)1010.generate .../boost-release/tools/build/v2/build-system.jam:736: in load .../boost-release/tools/build/v2/kernel/modules.jam:283: in import .../boost-release/tools/build/v2/kernel/bootstrap.jam:142: in boost-build .../boost-release/boost-build.jam:17: in module scope index.html libs/index.html more/getting_started.html tools/index.html I'm using the release branch. Does anyone know what the problem could be?

2 2

Release Managers: permission to merge small feature to release?
by Marshall Clow 19 Feb '13

19 Feb '13

I have a ticket <https://svn.boost.org/trac/boost/ticket/7652> asking for compile-time checked access to elements of a boost::array. I have implemented a specialization of boost::get (and for c++11, std::get) that does this, and it's been on the trunk and being tested for a couple weeks. This is technically not a bug fix, but new functionality, but I'd like to get it into the next release. So, I'm asking permission to merge to release. The change lists are 82083 (for the functionality), 82084 and 82102 (for the tests), and 82103 (for the docs) Thanks! -- Marshall

5 5

[Lockfree] ringbuffer
by Rich E 17 Feb '13

17 Feb '13

First off, all Boost.Lockfree tests in trunk are passing for me on clang 4.0 on OS X, hurrah! Thank you Tim for working on this for so long... I'm running through the examples now, only with the outdated documentation as a guide (more than a couple years old). I cannot find the ringbuffer container - was it renamed or removed altogether during the review period? I notice spsc_queue acts awefully like a ringbuffer, and it's implementation contains many

2 6

[fixed_point] Request for interest in a binary fixed point library
by Vicente J. Botet Escriba 02 Feb '13

02 Feb '13

Hi, the recent discussion on the MultiplePrecission Arithmetic library has show that some people has its ow fixed point library. Is there an interest in a Boost library having as base http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3352.html? I have started a prototype http://svn.boost.org/svn/boost/sandbox/fixed_point (there is no doc yet but the basic goal is quite close to the N3352 C++ proposal). This prototype should allow you to play a little bit with. If yes, what would you like to be changed, added or improved in n3352? Next follows some design decisions that IMO need to be decided before hand. * Should integers and reals be represented by separated classes? * Should signed and unsigned be represented by separated classes? * Should the library use a specific representation for signed numbers (separated sign, 2-complement? Let the user choose? * Should the library provide arbitrary range and resolution and allocators? * Should the library be open to overflow and rounding or just implement some of the possible policies? and in this case which ones? * Should fixed_point be convertible to/from integer/float/double? * Could the result of an arithmetic operation have more range and resolution than his arguments? * Is there a need for a specific I/O? * is there a need for radix other than 2 (binary)? * Should the library implement the basic functions, or should it imperatively implement the C++11 math functions? Could a first version just forward to the c++11 math functions? * Should the library support just one of the know ways to name a fixed-point, a U(a,b), nQm, ...? Provide some ways to move from one to another? * Could expect the same/better performances respect to hand written code? * What should be the size used by a fixed_point instance? _fast? _least? Should the user be able to decide which approach is better for his needs? * Which should be the namespace? boost? boost/fixed_point? boost/binary_fixed_point? boost/bfp? ... * others you can think of. Please, replay if you are interested, have some experience in the domain, good ideas, .. Best regards, Vicente

6 44

program_options: Support for open-end options
by ST 27 Jan '13

27 Jan '13

Hi, It would be great to implement support for open-end options, something like that: item_1 = 23 item_2 = 45 ... item_N = 465 The idea is to to be able to provide following input: configOptions.add_options() ("item_", value<int>(), "items"); now if add_options() sees a key that ends with a "_" it accepts all options with keys that start with item_, no matter what comes after it, and treat all of them as int . Nesting should also be possible - like this: "item_.subitem_.subsubitem_" (item_3.subitem_FOO.subsubitem_34 should be a valid option key). I can try to implement it, however only if it will have a chance to be merged into the boost library. Whom should I contact regarding this? Thank you, Simone

5 13

[1.53.0] Release Notes
by Daniel James 26 Jan '13

26 Jan '13

Hello everyone, Please can you send me your library's release notes for 1.53. Or if you prefer you can add them yourself to: http://svn.boost.org/svn/boost/website/public_html/live/feed/history/boost_… thanks, Daniel

9 13

Boost Support for Android and iOS
by rohit dhamija 25 Jan '13

25 Jan '13

Hi, Boost libraries are intended to be widely useful, and usable across a broad range of applications, but yet there is no official support available for Android and iOS 1. Is there any specific reason behind the same (like not optimized for embedded devices)? Or any other reason? 2. Are there (at all) any known issues if we use boost libraries for networking and thread synchronization for Smartphone application development ? Will it be a good idea to use BOOST ASIO for the same? I found some articles to compile boost but it would be great if we have some official links. FYI are the links found https://github.com/MysticTreeGames/Boost-for-Android http://www.codexperiments.com/android/2011/05/tips-tricks-building-boost-wi… RDX

10 10

[variant] Basic rvalue and C++11 features support
by Antony Polukhin 20 Jan '13

20 Jan '13

Hi, There is a patch in ticket #7620 that adds some rvalue assignment operators and rvalue constructors for Boost.Variant library. I saw no activity from authors of Boost.Variant Eric Friedman and Itay Maman for a long time, so if there will be no objections, I'll commit patch to trunk in the middle of November. Any suggestions and comments are welcomed. -- Best regards, Antony Polukhin

19 74

Changes to VS 2012 config
by Marshall Clow 17 Jan '13

17 Jan '13

Just so people know - I'm updating the Visual Studio configuration to more accurately reflect the capabilities of VS 2012. The first step was in http://svn.boost.org/trac/boost/changeset/81613 ; the next step will be to update the compiler features. If you see any problems, please let me know. -- Marshall

14 26

[parameter] std proposal
by Lorenzo Caminiti 07 Jan '13

07 Jan '13

Hello all, Is there a C++ standard proposal for named parameter addition? I am looking for an "N-paper" for named parameters similar to N2081 for concepts, or N1962 for contracts. Thank you. -- Sent from my mobile device Lorenzo

6 8

[utf8_codecvt_facet]
by Robert Ramey 06 Jan '13

06 Jan '13

change Revision: 81616 Author: marshall Date: 11:12:42 AM, Wednesday, November 28, 2012 Message: Fixed incorrect 'const' param for utf8_codecvt_facet::do_length ---- Modified : /trunk/boost/detail/utf8_codecvt_facet.hpp This change causes the a failure in the serialization library test suite with "test_utf8_codecvt" on all platforms which use the gcc standard library. I'm not sure what motivated the change or what it addressed but I'm pretty sure it's causing this (and a couple other) test failures. Note that all the failures are related to usage of wchar_t - perhaps that helps. Note that the test is part of the serialization library test suite - but it has nothing to do with serialization per se and doesn't use any of the serialization library. It just happens to be there because there was no more convenient place to put it. Marshall - could you please look into this? Robert Ramey

2 9

[Range] Proposal: a sub-maintainer of Boost.Range
by Michel Morin 05 Jan '13

05 Jan '13

Dear Neil, Dear Nate, First I'd like to say thank you for your library, Neil. It is a very useful library and it's great fun to writing codes with range adaptors. Boost.Range is one of the most important Boost libraries that are not yet added to the Standard. I know that Neil has made an effort to make time for developing the library, but recently making time for development seems difficult. And there are several open tickets of trivial bugs (e.g. #5603, #6110). Considering this situation, I'd like to make a proposal about Boost.Range: ** Adding a sub-maintainer to Boost.Range ** This reduces author's maintenance burden and also helps more stable development of the library. I recommend Nathan Ridge as a sub-maintainer of Boost.Range. His knowledge, experiences and contribution to Boost are great. If both of Neil and Nate accept the proposal, and if Nate needs some support for the start-up, I'll try my best to support him. I also believe that Jeff will also support him ;) Neil, what do you think about this proposal? I would appreciate and respect any of your reply. Yours sincerely, Michel

11 42

[smart_ptr] error with nullptr_t
by Vicente J. Botet Escriba 05 Jan '13

05 Jan '13

Hi, next follows a compile error with clang 3.1 c++11 just including #include <boost/shared_ptr.hpp> iMac-de-Vicente-Botet-Escriba:test viboes$ time bjam toolset=clang-3.1x ts_ -q ...patience... ...found 1100 targets... ...updating 50 targets... clang-darwin.compile.c++ ../../../bin.v2/libs/thread/test/test_so.test/clang-darwin-3.1x/debug/threading-multi/test_so.o In file included from ../example/test_so.cpp:6: In file included from ../../../boost/shared_ptr.hpp:17: ../../../boost/smart_ptr/shared_ptr.hpp:344:22: error: non-friend class member 'nullptr_t' cannot have a qualified name shared_ptr( std::nullptr_t ) BOOST_NOEXCEPT : px( 0 ), pn() // never throws ~~~~~^ ../../../boost/smart_ptr/shared_ptr.hpp:344:33: error: expected ';' at end of declaration list shared_ptr( std::nullptr_t ) BOOST_NOEXCEPT : px( 0 ), pn() // never throws ^ ;

9 22

[Release managers] Permission to rollback Boost.Thread breaking changes
by Vicente J. Botet Escriba 04 Jan '13

04 Jan '13

Hi, I would like to apply the following patch to trunk and release branch to avoid the Boost.Thread breaking changes. * [@http://svn.boost.org/trac/boost/ticket/6229 #6229] Rename the unique_future to future following the c++11. * [@http://svn.boost.org/trac/boost/ticket/6266 #6266] Breaking change: thread destructor should call terminate if joinable. * [@http://svn.boost.org/trac/boost/ticket/6269 #6269] Breaking change: thread move assignment should call terminate if joinable. This will let us the time to discuss the best way to manage with this breaking changes. Is someone against this late change? Best, Vicente svn diff boost/thread libs/thread Index: boost/thread/detail/config.hpp =================================================================== --- boost/thread/detail/config.hpp (revision 82295) +++ boost/thread/detail/config.hpp (working copy) @@ -78,9 +78,9 @@ #define BOOST_THREAD_RVALUE_REFERENCES_DONT_MATCH_FUNTION_PTR #endif -// Default version is 3 +// Default version #if !defined BOOST_THREAD_VERSION -#define BOOST_THREAD_VERSION 3 +#define BOOST_THREAD_VERSION 2 #else #if BOOST_THREAD_VERSION!=2 && BOOST_THREAD_VERSION!=3 && BOOST_THREAD_VERSION!=4 #error "BOOST_THREAD_VERSION must be 2, 3 or 4" Index: libs/thread/src/win32/thread.cpp =================================================================== --- libs/thread/src/win32/thread.cpp (revision 82295) +++ libs/thread/src/win32/thread.cpp (working copy) @@ -12,7 +12,7 @@ #ifndef WINVER #define WINVER 0x400 #endif -#define BOOST_THREAD_VERSION 3 +//#define BOOST_THREAD_VERSION 3 #include <boost/thread/thread.hpp> #include <boost/thread/once.hpp> Index: libs/thread/src/pthread/thread.cpp =================================================================== --- libs/thread/src/pthread/thread.cpp (revision 82295) +++ libs/thread/src/pthread/thread.cpp (working copy) @@ -6,7 +6,7 @@ // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -#define BOOST_THREAD_VERSION 3 +//#define BOOST_THREAD_VERSION 3 #include <boost/thread/detail/config.hpp> #include <boost/thread/thread.hpp>

2 9

Release managers: Boost.Thread breaking changes in 1.53
by Vicente J. Botet Escriba 04 Jan '13

04 Jan '13

Hi, there has been some threads about the following Boost.Thread breaking change in release 1.53. "Breaking changes when BOOST_THREAD_VERSION==3 (Default value since Boost 1.53): There are some new features which share the same interface but with different behavior. These breaking features are provided by default when BOOST_THREAD_VERSION is 3, but the user can however choose the version 2 behavior by defining the corresponding macro. As for the deprecated features, these broken features will be only available until boost 1.55. * [@http://svn.boost.org/trac/boost/ticket/6229 #6229] Rename the unique_future to future following the c++11. * [@http://svn.boost.org/trac/boost/ticket/6266 #6266] Breaking change: thread destructor should call terminate if joinable. * [@http://svn.boost.org/trac/boost/ticket/6269 #6269] Breaking change: thread move assignment should call terminate if joinable. " I would like to request advise from the release managers and of course the Boost community. Should I rollback the default to BOOST_THREAD_VERSION==3 for 1.53 and let the time to discuss the best way to manage with these breaking changes? Best, Vicente

21 40

[log] Most recent version
by Alexander Arhipenko 04 Jan '13

04 Jan '13

Hi, We're going to update boost.log sources in our code base. Could you please recommend what version to use? The code is taken from: https://boost-log.svn.sourceforge.net/svnroot/boost-log/. And currently I consider 3 options: branches/v1 branches/bleeding-edge trunk Thanks in advance. Regards

5 7

utf8_codecvt facet - volunteer opportuntiy
by Robert Ramey 03 Jan '13

03 Jan '13

Our implementation for a codecvt facet internal wide char to/from utf8 format requires some maintainence. We have our own implementation since 2001. Since then, the standard libary has come to specify some implementations and some libraries have implemented some or all of this aspect of the standard library. I've come to believe that we should: a) tweak our code to use the standard library implementations if they exist. b) tweak our code to use the names of the standard library implementation b) tweak our build so that our version replaces the the standard library implementation when and only when there is no standard implemenation available. This seemingly simple task is complicated by the following circumstances. a) The relationshp between UCS and Unicode is pretty confusing. b) The iterface for codecvt is confusing. c) a number of standard library implementations have non-conforming codecvt interface. d) a number of standard library implementations don't have any codecvt header at all. This is not a problem for our current implementation because we never import it. Anyone interested in working on this should contact Marshall, Beman or myself (in that precedance). Robert Ramey

2 1

[config] Proposed BOOST_NOEXCEPT_NOTHROW macro
by Beman Dawes 03 Jan '13

03 Jan '13

The three current BOOST_NOEXCEPT* macro variants miss the case where C++03 code has a "throw()" throw-specifier. Classes that derive from standard library exceptions need this to avoid breaking code on C++03 compilers. I'm not enamored with the BOOST_NOEXCEPT_NOTHROW name, so feel free to offer suggestions for alternate names. Here is the full set of macros: #ifdef BOOST_NO_NOEXCEPT # define BOOST_NOEXCEPT # define BOOST_NOEXCEPT_NOTHROW throw() <---- new macro # define BOOST_NOEXCEPT_IF(Predicate) # define BOOST_NOEXCEPT_EXPR(Expression) false #else # define BOOST_NOEXCEPT noexcept # define BOOST_NOEXCEPT_NOTHROW noexcept <---- new macro # define BOOST_NOEXCEPT_IF(Predicate) noexcept((Predicate)) # define BOOST_NOEXCEPT_EXPR(Expression) noexcept((Expression)) #endif Unless there are objections, I'll commit the changes Wednesday afternoon Eastern US time. --Beman

7 11

Flow-based programming library for Boost?
by Marcus Tomlinson 03 Jan '13

03 Jan '13

Is there any interest out there for a library that allows you to create fast, efficient flow-based programs with an easy-to-use object-oriented interface? (http://en.wikipedia.org/wiki/Flow-based_programming) I've created an open-source library that does this, called "DSPatch" ( http://sourceforge.net/projects/dspatch) and would like to contribute it to the Boost Libraries. Please let me know if this sounds like something you'd like to see in Boost. Thanks!

15 64

[GitHelp]TryModBoost gives fatal: reference is not a tree.
by Larry Evans 01 Jan '13

01 Jan '13

Trying the instructions here: https://svn.boost.org/trac/boost/wiki/TryModBoost resulted in an error at the `git submodule updata --init step. How can this be corrected? TIA. Larry Details of steps taken follow: ~/prog_dev/boost-modular $ git clone http://github.com/boost-lib/boost modular-boost Initialized empty Git repository in /home/evansl/prog_dev/boost-modular/modular-boost/.git/ remote: Counting objects: 8096, done. remote: Compressing objects: 100% (2982/2982), done. remote: Total 8096 (delta 5190), reused 8001 (delta 5095) Receiving objects: 100% (8096/8096), 1.98 MiB | 387 KiB/s, done. Resolving deltas: 100% (5190/5190), done. ~/prog_dev/boost-modular $ ls modular-boost ~/prog_dev/boost-modular $ cd modular-boost/ ~/prog_dev/boost-modular/modular-boost $ ls INSTALL boost.css bootstrap.sh index.html status Jamroot boost.png doc libs tools LICENSE_1_0.txt boostcpp.jam forward_headers.cmake more boost-build.jam bootstrap.bat index.htm rst.css ~/prog_dev/boost-modular/modular-boost $ git submodule update --init Submodule 'libs/accumulators' (git://github.com/boost-lib/accumulators.git) registered for path 'libs/accumulators' Submodule 'libs/algorithm' (git://github.com/boost-lib/algorithm.git) registered for path 'libs/algorithm' Submodule 'libs/any' (git://github.com/boost-lib/any.git) registered for path 'libs/any' Submodule 'libs/array' (git://github.com/boost-lib/array.git) registered for path 'libs/array' Submodule 'libs/asio' (git://github.com/boost-lib/asio.git) registered for path 'libs/asio' Submodule 'libs/assign' (git://github.com/boost-lib/assign.git) registered for path 'libs/assign' Submodule 'libs/atomic' (git://github.com/boost-lib/atomic.git) registered for path 'libs/atomic' Submodule 'libs/bimap' (git://github.com/boost-lib/bimap.git) registered for path 'libs/bimap' Submodule 'libs/bind' (git://github.com/boost-lib/bind.git) registered for path 'libs/bind' Submodule 'libs/chrono' (git://github.com/boost-lib/chrono.git) registered for path 'libs/chrono' Submodule 'libs/circular_buffer' (git://github.com/boost-lib/circular_buffer.git) registered for path 'libs/circular_buffer' Submodule 'libs/compatibility' (git://github.com/boost-lib/compatibility.git) registered for path 'libs/compatibility' Submodule 'libs/concept_check' (git://github.com/boost-lib/concept_check.git) registered for path 'libs/concept_check' Submodule 'libs/config' (git://github.com/boost-lib/config.git) registered for path 'libs/config' Submodule 'libs/container' (git://github.com/boost-lib/container.git) registered for path 'libs/container' Submodule 'libs/context' (git://github.com/boost-lib/context.git) registered for path 'libs/context' Submodule 'libs/conversion' (git://github.com/boost-lib/conversion.git) registered for path 'libs/conversion' Submodule 'libs/core' (git://github.com/boost-lib/core.git) registered for path 'libs/core' Submodule 'libs/coroutine' (git://github.com/boost-lib/coroutine.git) registered for path 'libs/coroutine' Submodule 'libs/crc' (git://github.com/boost-lib/crc.git) registered for path 'libs/crc' Submodule 'libs/date_time' (git://github.com/boost-lib/date_time.git) registered for path 'libs/date_time' Submodule 'libs/disjoint_sets' (git://github.com/boost-lib/disjoint_sets.git) registered for path 'libs/disjoint_sets' Submodule 'libs/dynamic_bitset' (git://github.com/boost-lib/dynamic_bitset.git) registered for path 'libs/dynamic_bitset' Submodule 'libs/exception' (git://github.com/boost-lib/exception.git) registered for path 'libs/exception' Submodule 'libs/filesystem' (git://github.com/boost-lib/filesystem.git) registered for path 'libs/filesystem' Submodule 'libs/flyweight' (git://github.com/boost-lib/flyweight.git) registered for path 'libs/flyweight' Submodule 'libs/foreach' (git://github.com/boost-lib/foreach.git) registered for path 'libs/foreach' Submodule 'libs/format' (git://github.com/boost-lib/format.git) registered for path 'libs/format' Submodule 'libs/function' (git://github.com/boost-lib/function.git) registered for path 'libs/function' Submodule 'libs/function_types' (git://github.com/boost-lib/function_types.git) registered for path 'libs/function_types' Submodule 'libs/functional' (git://github.com/boost-lib/functional.git) registered for path 'libs/functional' Submodule 'libs/functional_hash' (git://github.com/boost-lib/functional_hash.git) registered for path 'libs/functional_hash' Submodule 'libs/fusion' (git://github.com/boost-lib/fusion.git) registered for path 'libs/fusion' Submodule 'libs/geometry' (git://github.com/boost-lib/geometry.git) registered for path 'libs/geometry' Submodule 'libs/gil' (git://github.com/boost-lib/gil.git) registered for path 'libs/gil' Submodule 'libs/graph' (git://github.com/boost-lib/graph.git) registered for path 'libs/graph' Submodule 'libs/graph_parallel' (git://github.com/boost-lib/graph_parallel.git) registered for path 'libs/graph_parallel' Submodule 'libs/heap' (git://github.com/boost-lib/heap.git) registered for path 'libs/heap' Submodule 'libs/icl' (git://github.com/boost-lib/icl.git) registered for path 'libs/icl' Submodule 'libs/integer' (git://github.com/boost-lib/integer.git) registered for path 'libs/integer' Submodule 'libs/interprocess' (git://github.com/boost-lib/interprocess.git) registered for path 'libs/interprocess' Submodule 'libs/intrusive' (git://github.com/boost-lib/intrusive.git) registered for path 'libs/intrusive' Submodule 'libs/io' (git://github.com/boost-lib/io.git) registered for path 'libs/io' Submodule 'libs/iostreams' (git://github.com/boost-lib/iostreams.git) registered for path 'libs/iostreams' Submodule 'libs/iterator' (git://github.com/boost-lib/iterator.git) registered for path 'libs/iterator' Submodule 'libs/lambda' (git://github.com/boost-lib/lambda.git) registered for path 'libs/lambda' Submodule 'libs/local_function' (git://github.com/boost-lib/local_function.git) registered for path 'libs/local_function' Submodule 'libs/locale' (git://github.com/boost-lib/locale.git) registered for path 'libs/locale' Submodule 'libs/lockfree' (git://github.com/boost-lib/lockfree.git) registered for path 'libs/lockfree' Submodule 'libs/logic' (git://github.com/boost-lib/logic.git) registered for path 'libs/logic' Submodule 'libs/math' (git://github.com/boost-lib/math.git) registered for path 'libs/math' Submodule 'libs/move' (git://github.com/boost-lib/move.git) registered for path 'libs/move' Submodule 'libs/mpi' (git://github.com/boost-lib/mpi.git) registered for path 'libs/mpi' Submodule 'libs/mpl' (git://github.com/boost-lib/mpl.git) registered for path 'libs/mpl' Submodule 'libs/msm' (git://github.com/boost-lib/msm.git) registered for path 'libs/msm' Submodule 'libs/multi_array' (git://github.com/boost-lib/multi_array.git) registered for path 'libs/multi_array' Submodule 'libs/multi_index' (git://github.com/boost-lib/multi_index.git) registered for path 'libs/multi_index' Submodule 'libs/multiprecision' (git://github.com/boost-lib/multiprecision.git) registered for path 'libs/multiprecision' Submodule 'libs/numeric/conversion' (git://github.com/boost-lib/numeric_conversion.git) registered for path 'libs/numeric/conversion' Submodule 'libs/numeric/interval' (git://github.com/boost-lib/interval.git) registered for path 'libs/numeric/interval' Submodule 'libs/numeric/odeint' (git://github.com/boost-lib/odeint.git) registered for path 'libs/numeric/odeint' Submodule 'libs/numeric/ublas' (git://github.com/boost-lib/ublas.git) registered for path 'libs/numeric/ublas' Submodule 'libs/optional' (git://github.com/boost-lib/optional.git) registered for path 'libs/optional' Submodule 'libs/parameter' (git://github.com/boost-lib/parameter.git) registered for path 'libs/parameter' Submodule 'libs/phoenix' (git://github.com/boost-lib/phoenix.git) registered for path 'libs/phoenix' Submodule 'libs/polygon' (git://github.com/boost-lib/polygon.git) registered for path 'libs/polygon' Submodule 'libs/pool' (git://github.com/boost-lib/pool.git) registered for path 'libs/pool' Submodule 'libs/preprocessor' (git://github.com/boost-lib/preprocessor.git) registered for path 'libs/preprocessor' Submodule 'libs/program_options' (git://github.com/boost-lib/program_options.git) registered for path 'libs/program_options' Submodule 'libs/property_map' (git://github.com/boost-lib/property_map.git) registered for path 'libs/property_map' Submodule 'libs/property_tree' (git://github.com/boost-lib/property_tree.git) registered for path 'libs/property_tree' Submodule 'libs/proto' (git://github.com/boost-lib/proto.git) registered for path 'libs/proto' Submodule 'libs/ptr_container' (git://github.com/boost-lib/ptr_container.git) registered for path 'libs/ptr_container' Submodule 'libs/python' (git://github.com/boost-lib/python.git) registered for path 'libs/python' Submodule 'libs/random' (git://github.com/boost-lib/random.git) registered for path 'libs/random' Submodule 'libs/range' (git://github.com/boost-lib/range.git) registered for path 'libs/range' Submodule 'libs/ratio' (git://github.com/boost-lib/ratio.git) registered for path 'libs/ratio' Submodule 'libs/rational' (git://github.com/boost-lib/rational.git) registered for path 'libs/rational' Submodule 'libs/regex' (git://github.com/boost-lib/regex.git) registered for path 'libs/regex' Submodule 'libs/scope_exit' (git://github.com/boost-lib/scope_exit.git) registered for path 'libs/scope_exit' Submodule 'libs/serialization' (git://github.com/boost-lib/serialization.git) registered for path 'libs/serialization' Submodule 'libs/signals' (git://github.com/boost-lib/signals.git) registered for path 'libs/signals' Submodule 'libs/signals2' (git://github.com/boost-lib/signals2.git) registered for path 'libs/signals2' Submodule 'libs/smart_ptr' (git://github.com/boost-lib/smart_ptr.git) registered for path 'libs/smart_ptr' Submodule 'libs/spirit' (git://github.com/boost-lib/spirit.git) registered for path 'libs/spirit' Submodule 'libs/spirit_classic' (git://github.com/boost-lib/spirit_classic.git) registered for path 'libs/spirit_classic' Submodule 'libs/statechart' (git://github.com/boost-lib/statechart.git) registered for path 'libs/statechart' Submodule 'libs/static_assert' (git://github.com/boost-lib/static_assert.git) registered for path 'libs/static_assert' Submodule 'libs/system' (git://github.com/boost-lib/system.git) registered for path 'libs/system' Submodule 'libs/test' (git://github.com/boost-lib/test.git) registered for path 'libs/test' Submodule 'libs/thread' (git://github.com/boost-lib/thread.git) registered for path 'libs/thread' Submodule 'libs/timer' (git://github.com/boost-lib/timer.git) registered for path 'libs/timer' Submodule 'libs/tokenizer' (git://github.com/boost-lib/tokenizer.git) registered for path 'libs/tokenizer' Submodule 'libs/tr1' (git://github.com/boost-lib/tr1.git) registered for path 'libs/tr1' Submodule 'libs/tti' (git://github.com/boost-lib/tti.git) registered for path 'libs/tti' Submodule 'libs/tuple' (git://github.com/boost-lib/tuple.git) registered for path 'libs/tuple' Submodule 'libs/type_traits' (git://github.com/boost-lib/type_traits.git) registered for path 'libs/type_traits' Submodule 'libs/typeof' (git://github.com/boost-lib/typeof.git) registered for path 'libs/typeof' Submodule 'libs/units' (git://github.com/boost-lib/units.git) registered for path 'libs/units' Submodule 'libs/unordered' (git://github.com/boost-lib/unordered.git) registered for path 'libs/unordered' Submodule 'libs/utility' (git://github.com/boost-lib/utility.git) registered for path 'libs/utility' Submodule 'libs/uuid' (git://github.com/boost-lib/uuid.git) registered for path 'libs/uuid' Submodule 'libs/variant' (git://github.com/boost-lib/variant.git) registered for path 'libs/variant' Submodule 'libs/wave' (git://github.com/boost-lib/wave.git) registered for path 'libs/wave' Submodule 'libs/xpressive' (git://github.com/boost-lib/xpressive.git) registered for path 'libs/xpressive' Submodule 'tools/auto_index' (git://github.com/boost-lib/auto_index.git) registered for path 'tools/auto_index' Submodule 'tools/bcp' (git://github.com/boost-lib/bcp.git) registered for path 'tools/bcp' Submodule 'tools/boostbook' (git://github.com/boost-lib/boostbook.git) registered for path 'tools/boostbook' Submodule 'tools/build' (git://github.com/boost-lib/build.git) registered for path 'tools/build' Submodule 'tools/inspect' (git://github.com/boost-lib/inspect.git) registered for path 'tools/inspect' Submodule 'tools/litre' (git://github.com/boost-lib/litre.git) registered for path 'tools/litre' Submodule 'tools/quickbook' (git://github.com/boost-lib/quickbook.git) registered for path 'tools/quickbook' Initialized empty Git repository in /home/evansl/prog_dev/boost-modular/modular-boost/libs/accumulators/.git/ remote: Counting objects: 475, done. remote: Compressing objects: 100% (201/201), done. remote: Total 475 (delta 319), reused 407 (delta 252) Receiving objects: 100% (475/475), 204.69 KiB | 335 KiB/s, done. Resolving deltas: 100% (319/319), done. Submodule path 'libs/accumulators': checked out '853400b2e1b4321696a90184d49cbb6610738806' Initialized empty Git repository in /home/evansl/prog_dev/boost-modular/modular-boost/libs/algorithm/.git/ remote: Counting objects: 681, done. remote: Compressing objects: 100% (370/370), done. remote: Total 681 (delta 392), reused 544 (delta 255) Receiving objects: 100% (681/681), 1.66 MiB | 383 KiB/s, done. Resolving deltas: 100% (392/392), done. fatal: reference is not a tree: a601c9ad632035076bb3c0feee75e915cfb54fca Unable to checkout 'a601c9ad632035076bb3c0feee75e915cfb54fca' in submodule path 'libs/algorithm'

2 1

[string_ref] Feature requests
by Daniel James 01 Jan '13

01 Jan '13

Hi, I've been trying to convert quickbook to use boost::string_ref, and there are a few missing features that might be useful: Construction from a pair of iterators, either std::basic_string::const_iterator, or boost::basic_string_ref::const_iterator. Which of course can be the same type, which is annoying but not too hard to work around. Easy conversion to std::basic_string. There's a C++11 explicit string operator, but that isn't much good for portable code. Something like a 'string' or 'to_string' member would do the trick. Support for comparisons with std::basic_string. The comparison operators are templates so they aren't called with an implicit conversion. Could use a template parameter for the type so that it picks up anything which is (implicitly?) convertible to boost::basic_string_ref, maybe using SFINAE. I didn't need it, but could probably also could do with a 'hash_value' function for boost::hash support. Is potentially error prone if the original string is modified or destroy, but there are some valid use cases. thanks, Daniel

4 13

[exception][iostream] link error in boost_1_52_0
by Jeff Flinn 31 Dec '12

31 Dec '12

I'm getting the following link error using boost_1_52_0 with Xcode 3.2.6 gcc 4.2: "std::bad_alloc::what() const", referenced from: vtable for boost::exception_detail::error_info_injector<std::bad_alloc>in libboost_iostreams-mt.a(zlib.o) vtable for boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<std::bad_alloc> >in libboost_iostreams-mt.a(zlib.o) Boost exception is listed as a header only library, but there is clone_current_exception_non_intrusive.cpp in ..\boost_1_52_0\libs\exception\src. Does boost.exception lib need to be built? thanks, jeff

2 2

[trunk] permission denied?
by Oliver Kowalke 31 Dec '12

31 Dec '12

Did you reset the passwords for trunk? Until today I was able to commit changes to boost-trunk - but my password is invalid now?! Oliver

7 9

[Git] Regression testing modular Boost
by Beman Dawes 30 Dec '12

30 Dec '12

Starting a new thread - this is far to important to bury in the long documentation thread! On Tue, Dec 11, 2012 at 10:52 AM, Rene Rivera <grafikrobot(a)gmail.com> wrote: >What is the procedure that testers will follow? I've been assuming testers will follow the same general procedure. But other than verifying that hand-invoked b2 runs tests as expected, nothing else has been done that I'm aware of. > Is there documentation equivalent to < > http://www.boost.org/development/running_regression_tests.html> for the new > setup? None yet. I've been assuming we will just update www.boost.org/development/running_regression_tests.html > What changes to the current tools need to happen to the adjust to > the new setup? As a first cut, branch the current tools and convert any code that currently uses svn commands to use git commands. But before any testing is done, it would be helpful if Boost.Build was updated to handle the generation of boost-root/boost header file links, rather than relying on the workaround cmake script. Do you feel comfortable enough with git to handle the conversion? --Beman

6 22

[Trac] Internal Server Error
by Vicente J. Botet Escriba 30 Dec '12

30 Dec '12

Hi, I'm getting a Internal Server Error TracError: IOError: [Errno 13] Permission denied: u'/opt/trac/boost/log/trac.log Could someone take a look? Vicente

1 0

[type_traits] Typo in Boost.TypeTraits
by Michel Morin 30 Dec '12

30 Dec '12

Patch attached for fixing typos in Boost.TypeTraits P.S. John, could you also apply the patch attached in #7683? https://svn.boost.org/trac/boost/ticket/7683 Regards, Michel

3 5

[algorithm] Typo in Boost.Algorithm
by Michel Morin 30 Dec '12

30 Dec '12

Patch attached for fixing typos in Boost.Algorithm P.S. Marshall, could you also apply the patch attached in #7714? https://svn.boost.org/trac/boost/ticket/7714 Regards, Michel

2 2

[Git] Modularization of Boost.Any, Boost.Array, and Boost.StaticAssert
by Daniel Pfeifer 29 Dec '12

29 Dec '12

Hi, according to our preliminary modularization, the candidates Boost.Any, Boost.Array, and Boost.StaticAssert each have their own repository, even though each of them consists of a single header file only (disregarding tests, examples and documentation). I propose to put all three of them into the Boost.Utility repository. Comments? --Daniel

7 9

[git] Boost.Build location
by Vladimir Prus 29 Dec '12

29 Dec '12

I am wondering what will be the location of Boost.Build after the git switch. It seems to be part of http://github.com/boost-lib/boost right now. Maybe, it would be best to have separate git repository for Boost.Build? In particular, that would allow to fork just Boost.Build, which is important given git's inability to handle partial checkouts. It would also allow giving push access for Boost.Build to other people, without also giving access to superproject. Comments? Thanks, Volodya

18 44

[python] Proposal: RAII for Global Interpreter Lock (GIL)
by John Zwinck 29 Dec '12

29 Dec '12

There are many questions and example classes online for dealing with Python's Global Interpreter Lock (GIL) using RAII. I think Boost.Python should provide this functionality, rather than having users who build hybrid C++/Python applications copy-pasting code from various places. I was one of those users recently, and the code I developed to deal with it is now public: https://github.com/jzwinck/pccl/blob/master/InterpreterLockGuard.hpp https://github.com/jzwinck/pccl/blob/master/InterpreterLockGuard.cpp https://github.com/jzwinck/pccl/blob/master/test/InterpreterLockGuard.test.… Comments in the header explain how to use it in the context of Boost.Python, and contain a link to a wiki from which some of the code was originally copied. Why add this to Boost? It's clearly code that a bunch of people need, often people who are already using Boost.Python. It has a permissive license, and I can re-license it if need be. And it depends on Boost (mostly for thread-specific storage--I hope this dependency won't be seen as a liability here, though it could be removed if needed). This particular implementation was used successfully in a few programs in a commercial setting on Fedora and RHEL systems. It has some extra checks that we found helpful compared to some of the versions you'll find posted online. The code also builds and passes its tests with GCC on Mac OS X. I welcome any feedback regarding the suitability for inclusion in Boost of this particular code and/or the concepts it implements. John Zwinck

2 2

Interest in serialization library
by iwg molw5 28 Dec '12

28 Dec '12

I recently wrote a small C++11 template library to unify the specification and construction of a serializable object. The library introduces a simple template markup language used to specify the layout of data on the wire, using that specification to construct the type in question much like a named tuple. A sample of the syntax used by the library is provided below: struct Object : serializable <Object, value <NAME("Field 1"), little_endian <uint32_t>>, value <NAME("Field 2"), big_endian <uint32_t>>> { }; The library is available under the MIT license at: http://www.github.com/molw5/framework with associated documentation located at: http://molw5.github.com/framework Is there any interest in including this library in Boost?

3 10

boost-commit list down?
by Marshall Clow 28 Dec '12

28 Dec '12

The last message I got from boost-commits was: Author: apolukhin Date: 2012-12-27 13:54:28 EST (Thu, 27 Dec 2012) New Revision: 82224 URL: http://svn.boost.org/trac/boost/changeset/82224 The archives at http://lists.boost.org/boost-commit/2012/12/date.php only go through revision 82223. -- Marshall

1 0

[odeint] Typo in Boost.Odeint
by Michel Morin 28 Dec '12

28 Dec '12

Boost.Odeint contains nearly 200 typos! Patch attached in #7835 https://svn.boost.org/trac/boost/ticket/7835 (I don't know why but the owner of odeint is empty in the ticket.) Regards, Michel

2 1

Re: [boost] [GitHelp] Sandbox library to GitHub
by Brian Wood 28 Dec '12

28 Dec '12

Edward Diener: > >On 12/26/2012 5:10 AM, Daniel Pfeifer wrote: >> 2012/12/26 Andrey Semashev <andrey.semashev(a)gmail.com>: >>> >>> Perhaps you didn't set up a ssh public key? >>> >>> https://help.github.com/articles/generating-ssh-keys#platform-windows >>> >>> You will also have to add the key to TortoiseGit/PuTTY. >> >> If you push over HTTPS, you don't need an ssh key. > > That sounds like what I want to do. The whole low-level business of > generating public/private keys, when I already have signed up for GitHub > with a username/password, seems silly to me. I know the Linux gurus all > love this kind of intricate stuff, but I do not. It's one command: ssh-keygen -t rsa -C "username(a)email.net" If you have Cygwin installed on Windows you can use the same command there. -- Brian Ebenezer Enterprises -- in G-d we trust. http://webEbenezer.net (651) 251-9384

2 1

[thread] to std:: or not to std::
by Michael Caisse 27 Dec '12

27 Dec '12

There seems to be a trend to migrate boost::thread to std::thread. Has there been consideration that perhaps the user community may not want this? There are differing opinions on threads (obviously) and recent breaking changes concern me. For example, the thread destructor now calling terminate instead of detach has made the upgrade to 1.52 more troublesome than it should have been. Will the next move be to remove interruption points? We have purposely selected Boost.Thread on a few projects that are also using C++11 because we prefer the Boost.Thread behaviour and feature set. The purpose of this email isn't to debate the merit of the Boost.Thread feature set but instead to understand the future direction of the library. Can Vicente or someone provide the intended road map or general plan for the library? Thanks! michael -- Michael Caisse ciere consulting ciere.com

4 9

Patch for functional/hash
by Thomas Heller 27 Dec '12

27 Dec '12

Hi, Attached is a patch for functional/hash. The first chunk essentially gets rid of some UB (the same technique was already applied for the remainder so this looks like an oversight). I don't remember why exactly i added the second chunk, it helps on some compilers though (I think gcc on Android). Save to apply that patch? Regards, Thomas

2 2

[proposal] safe_ref<T>
by Fernando Pelliccioni 27 Dec '12

27 Dec '12

Hi all, The motivation is to avoid code like the following... //---------------------------------------------------------------------------- #include <iostream> #include <string> struct A { void do_something( std::string s ) const { std::cout << "do something with " << s << " and " << i_ << "\n"; } int i_ = 99; }; // unsafe traditional code struct Unsafe { void set_ref( A& a ) { a_ptr_ = std::addressof(a); } void use_ref( std::string s ) const { if (a_ptr_ != nullptr) { a_ptr_->do_something(s); } } void use_ref_2( std::string s ) const { //forgot to check for nullptr a_ptr_->do_something(s); } A* a_ptr_ = nullptr; //I can't use A& nor reference_wrapper<A>, need to be nullable. }; void f() { A a; Unsafe unsafe; unsafe.use_ref( "hello" ); //null reference, do nothing, hope! unsafe.set_ref(a); unsafe.use_ref( "hello world!" ); //not-null reference, Ok! Unsafe unsafe2; unsafe2.use_ref( "hello" ); //null reference, do nothing, hope! unsafe2.use_ref_2( "hello" ); //null reference, Ops! } //---------------------------------------------------------------------------- The proposed solution: //---------------------------------------------------------------------------- // Proposed (draft) //---------------------------------------------------------------------------- template <typename T> class safe_ref { public: typedef T type; explicit safe_ref() : t_( nullptr ) {} explicit safe_ref(T& t) : t_( std::addressof(t) ) {} template <typename Func> void use ( Func f ) const { if ( is_initialized() ) { f( *t_ ); } } private: bool is_initialized() const { return t_ != nullptr; } T* t_; }; template <typename T> inline safe_ref<T> const ref(T& t) { return safe_ref<T>(t); } template <typename T> inline safe_ref<T const> const cref(T const& t) { return safe_ref<T const>(t); } //---------------------------------------------------------------------------- // Usage //---------------------------------------------------------------------------- #include <iostream> #include <string> struct A { void do_something( std::string s ) const { std::cout << "A::do_something with " << s << " and " << i_ << "\n"; } int i_ = 99; }; struct Safe { void set_ref( A& a ) { a_ref_ = ref(a); } void use_ref( std::string s ) const { a_ref_.use( [&s] ( A& a ) { a.do_something(s); }); } safe_ref<A> a_ref_; }; void usage1() { A a; Safe safe; safe.use_ref( "hello" ); //null reference, do nothing safe.set_ref(a); safe.use_ref( "hello world!" ); //safe reference, Ok! } void usage2() { safe_ref<int> si; si.use( [] (int& i ) { std::cout << i << std::endl; }); int temp = 15; safe_ref<int> si2(temp); si2.use( [] (int& i ) { std::cout << i << std::endl; }); si = ref(temp); si.use( [] (int& i ) { std::cout << i << std::endl; }); } //---------------------------------------------------------------------------- It is similar to optional<T>, but in this case the idea is to not allow access to internal data if the pointer is null, only allowing a safe usage There is interest to add something like this to Boost? Any comments or remarks? Thanks and regards, Fernando Pelliccioni.

5 6

[GitHelp] Sandbox library to GitHub
by Edward Diener 27 Dec '12

27 Dec '12

Under Windows following the instructions at https://svn.boost.org/trac/boost/wiki/ExtractSandbox for moving an SVN sandbox library to GitHub I am successful in the first step of cloning SVN sandbox library to a temporary local directory. But when I go to that local directory and try: git push --mirror git@github.com:eldiener/variadic_macro_data.git I receive a PuTTY message of: "Disconnected: No supported authentication methods available (server sent: publickey)" I have no idea how PuTTY gets into this. I am using TortoiseGit and Git for Windows and evidently getting Git to work under Windows is difficult in some way. Anybody have any idea how to straighten this out ?

4 6

[git] What about unmaintained libraries?
by Andrey Semashev 26 Dec '12

26 Dec '12

Hi, I have little experience with git and none with GitHub, so apologies if my questions sound silly. We have a number of unmaintained libraries in Boost. With svn anyone with commit rights can apply fixes and even take over these libs. In the end of the day, I think, this is a good thing - community support is better than no support. Even with maintained libs, it is sometimes simpler to just apply the fix instead of filing a ticket and waiting for the maintainer to get to it. Also, remember the bug fixing weeks we had a while ago - anyone could choose a library and resolve tickets against it. I'm not sure how this will work after transition to git. IIUC, every lib will be extracted into a separate git repository, and presumably only the library maintainer will have the commit rights to that repo. Essentially this means that unmaintained libs will become immutable after the transition. Also, every minor fix will have to go through the library maintainer, however busy he may be. I suppose the problem with unmaintained libs could be solved by forking but what if noone is ready to become the official maintainer but occasionally people commit fixes and improvements to the lib? I believe, at least Boost.DateTime is currently in such situation. Also, forking does not solve the problem for minor fixes to maintained libs. I would really like it if there was some kind of a user group (of all Boost maintainers) that could be used to grant commit rights to the libraries. Whatever the git term is, by "commit" here I mean the ability to publish the changes to the repository on GitHub, so that they are visible to other developers, including monolithic Boost release scripts. Is this possible? If yes, I think all repositories produced as a result of the transition to git should grant commit rights to this group by default, so that the access rights are the same as with svn now.

4 7

[move] uninitialized_move
by Adam Wulkiewicz 26 Dec '12

26 Dec '12

Hi, I recently saw how boost::uninitialized_move is implemented, it doesn't check for exceptions thrown by move ctor and don't delete already constructed objects. Is this intentional? Regards, Adam

2 2

Boost SIMD beta release
by joel falcou 25 Dec '12

25 Dec '12

We're rolling a beta release of Boost.SIMD along with a beta release of NT2. This version comes very late because we were busy with other things but hopefully we'll now do rolling releases frequently. Documentation is quite lacking but code is relatively stable and works. * Release Files can be found here: http://nt2.metascale.org/downloads/ * Additional material about the library can be found here : - Boost.SIMD PACT paper : http://www.lri.fr/~falcou/pub/pact-2012.pdf - Boost.SIMD MeetingC++ slides : http://meetingcpp.com/tl_files/mcpp/slides/12/simd.pdf * We welcome comments, questions and random requests/rants/bug reports as to polish the library before actual submission to the boost review. Such comments can be sent there, on our nt2-dev Google groups or in the nt2 issue tracker. Regards

13 57

automatic SVN mirror down?
by Robin Eckert 24 Dec '12

24 Dec '12

Hello, The latest commit on the live boost SVN mirror (git://github.com/ryppl/boost-svn.git) is 11 days old. Is the automatic mirror jammed right now or is the mirror probably shut down due to the modularization effort? Regards, Robin

2 2

[GitHelp] Help desk ready to assist
by Beman Dawes 24 Dec '12

24 Dec '12

See https://svn.boost.org/trac/boost/wiki/GitHelp for details. --Beman

1 0

[Git] ** Attention All Boost Committers **
by Dave Abrahams 24 Dec '12

24 Dec '12

If you have *ever* checked *anything* (e.g. code or documentation) into the Boost Subversion repository, this message applies to you. Git uses email addresses to identify authors and committers. In order to accurately convert Subversion history to Git, we need to map all (or as many as possible) Subversion user IDs to working email addresses. I have posted a provisional UserID mapping table at https://github.com/boost-lib/boost/wiki/AuthorMapping (with a simple mangling of '@'=>'<>' and '.'=>'~'). If your email address is already in the table, you've been Bcc'd on this message, which may explain the appearance of multiple copies in your mailbox. I request that you make corrections to this table. To edit the table directly, you'll need to be logged into GitHub. Direct correction is by far the preferable approach, but if you don't have---and don't want to acquire---a free GitHub account, you can send edits directly to me. Important notes (these also appear on the page with the table) * You may have several userids (e.g. I appear to have "dave," "abrahams," and "david_abrahams" --- probably left over from the transition from SourceForge CVS to our own SVN). Please look carefully to be sure that you have accounted for all your userids, and please use the same name and email address for each of them. Please *make sure that all non-duplicate userids stay in the table*. For example, all three of my userids are still there. * A given userid may appear several times in the table. If that userid belongs to you, please delete all but one line. If you don't, we will just use the first entry with that userid. * If you have a GitHub account, please make sure the email address you use in the table is associated with that account at https://github.com/settings/emails Thanks for your cooperation. -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost

3 2

[TypeErasure] Similar simple class.
by Arman Hunanyan 23 Dec '12

23 Dec '12

Hi All, I have implemented xany class https://sourceforge.net/projects/extendableany/?source=directory. Then I noticed that there is a Boost.TypeErasure library which allows to do same as xany does and something more. Implementation of class xany has 1005 lines and it is implemented and tested in a week. Of course xany isn't comparable with Boost.TypeErasure, but it may be interesting to look. Below is a definition of same method for Boost.TypeErasure and for xany. // definition of push_back for Boost.TypeErasure template<class C, class T> struct push_back { static void apply(C& cont, const T& arg) { cont.push_back(arg); } }; namespace boost { namespace type_erasure { template<class C, class T, class Base> struct concept_interface< ::push_back<C, T>, Base, C> : Base { void push_back(typename rebind_any<Base, const T&>::type arg) { call(::push_back<C, T>(), *this, arg); } }; } } any<push_back<_self, int>, _self&> c; // definition of push_back for xany template <typename Xany, typename T> struct push_back_method { typedef void (Xany::* signature) (const T&); template <typename B> struct wrapper : public B { void push_back(const T& e) { this->call(push_back_method(), e); } }; struct implementation { template <typename Container> void operator() (Container& c, const T& e) { c.push_back(e); } }; }; xany<boost::mpl::vector<push_back_method<boost::mpl::_1, int> > > c; xany requires additional signature type to be specified. This allows to use dispatching in implementation. struct implementation { void operator() (OtherCodingStyleContainer& c, const T& e) { c.PushBack(e); } template <typename Container> void operator() (Container& c, const T& e) { c.push_back(e); } }; Documentation contains more examples.

1 0

[Inspect] hadn't run since... August
by Artyom Beilis 23 Dec '12

23 Dec '12

Boost.Inspect hadn't run on trunk or release sinse august: From: http://beta.boost.org/development/testing.html trunk - http://boost.cowic.de/rc/inspect-trunk.html release - http://boost.cowic.de/rc/inspect-snapshot.html Artyom Beilis -------------- CppCMS - C++ Web Framework: http://cppcms.com/ CppDB - C++ SQL Connectivity: http://cppcms.com/sql/cppdb/

2 1

[atomic, x86] need another pair of eyes
by Tim Blechmann 23 Dec '12

23 Dec '12

hi all, i need another pair of eyes regarding boost.atomic on x86: the implementation of memory barrier is merely a compiler barrier, but not a CPU barrier, as it is using code like: __asm__ __volatile__ ("" ::: "memory"); afaict, one should use a `real' CPU barrier like "mfence" or "lock; addl $0,0(%%esp)". is this correct? apart from that, i've seen that compare_exchange is using explicit memory barriers before/after "cmpxchg" instructions. i somehow though that cmpxchg and the 8b/16b variants implicitly issue a memory barrier, so the resulting code would generate multiple memory barriers. can someone with some insights in the x86 architecture confirm this? thanks, tim

6 35

Re: [boost] Boost SIMD beta release
by Brian Wood 23 Dec '12

23 Dec '12

From: Mathias Gaunard: On 20/12/2012 20:34, Dave Abrahams wrote: >> Yes; there's a runtime test. > > Let's put a runtime test at every step of our critical loop, sounds like > a good idea. > I actually somewhat looked into this, and in this case segmented > iterators don't allow any optimization compared to normal iterators. I think less sarcasm would be helpful. >> I'm afraid you have not been specific enough about the >> problem you claim to see for me to be able to evaluate >> whether it exists or not. > > I'm afraid you're the one trying to make everything fit into this > model you've somehow taken a liking to. I'd prefer to focus on results rather than motives. Shalom Brian Ebenezer Enterprises http://webEbenezer.net (651) 251-9384

1 0

[BTREE] Get BTREE library into boost - Market Research
by Joel Young 22 Dec '12

22 Dec '12

My organization is investigating contracting for enhancements to the boost::btree library developed by Beman Dawes with all enhancements to remain under the boost license and author(s) retaining all copyright. No travel is expected to be required as part of this project. We are considering the following enhancements: 1. Develop detailed developer and tutorial documentation in customary boost formats 2. Enhancing the interface to provide more explicit preload and caching control to include the amount of RAM to reserve, perhaps with the ability to specify posix alignment to maximize benefit of linux anonymous huge page support. 3. Make the library C++ 11 ready 4. Finalize data layout and support for variable length payloads 5. Provide convenient interface for storing std::string (or the contents thereof) in payloads 6. Prepare the library for submission for formal review Any comments and suggestions on this are greatly appreciated. Of particular interest are discussions of technical approaches and estimates of hours required. Please do not send formal proposals. In addition to replying on this list (preferred) I can be reached at the telephone numbers and email below. Comments sent by 21 December will be most valuable. Discussion after that is still very welcome! Please don’t include any proprietary data. Also note that I am not authorized to commit the government in any way--this is simply market research. Thanks! Joel Dr. JOEL D. YOUNG Assistant Professor Computer Science Department Naval Postgraduate School Glasgow East Rm 338 jdyoung(a)nps.edu (831) 656-3518

6 11

Security bugs policy
by Artyom Beilis 22 Dec '12

22 Dec '12

Hello, I would like to know if there is any policy about security bug fixes, updates or releases. What I'm talking about. Consider a security related bug discovered in boost library. For example: For example recently reported bug in Boost.Locale that will be fixed in 1.53 https://svn.boost.org/trac/boost/ticket/7743 I consider it security bug as an application that validates the input (checks if it is UTF-8) may accept an invalid sequence. Or very critical bug in UUID (fixed in 1.43): https://svn.boost.org/trac/boost/ticket/3971 That any application that used them may be target to UUID guessing. These kind of bugs in general should be considered critical and somehow published, it may be also important to backport the fixes to stable releases, because not everybody can move forward and they may need to stick with older releases (as Boost is neither ABI nor API backward compatible even between minor releases). Annoucements of such bugs may be critical for example for stable Linux distributions that ship some older Boost versions and likely need to backport such bug fixes to their own boost tree because Boost doesn't do it. Questions: - Do we have any policy about it? - If not we probably need one including backporting of security bug fixes to stable releases. What brings me to other issues... Should Boost support older releases with critical bug fixes/security bug fixes? For how long time? Artyom Beilis -------------- CppCMS - C++ Web Framework: http://cppcms.com/ CppDB - C++ SQL Connectivity: http://cppcms.com/sql/cppdb/

2 1

Question about test failures
by Andrey Semashev 22 Dec '12

22 Dec '12

Hi, I've been looking through Boost.Atomic test results [1] and saw that all tests on IBM_Canada_Ltd are marked as failed. The test result [2] refer to Boost.Thread build results [3] which I think is supposed to mean that the test failed because the dependent library failed to build. However, the Boost.Thread build report is marked as succeeded. I'm not sure how to interpret these results. Can someone clarify this? Thank you. [1] http://www.boost.org/development/tests/trunk/developer/atomic.html [2] http://www.boost.org/development/tests/trunk/developer/output/IBM_Canada_Lt… [3] http://www.boost.org/development/tests/trunk/output/IBM_Canada_Ltd-boost-bi…

1 0

[release] add comments/changes
by Oliver Kowalke 21 Dec '12

21 Dec '12

Which files do I've to use in order to add notes about changes and new features of the next release? thx, Oliver

2 1

[Git] Extracting libraries from the svn sandbox
by Beman Dawes 20 Dec '12

20 Dec '12

One of the issues that came up in the documentation discussion was the desire to extract still useful sub-trees from the old svn sandbox, and to move them to GitHub. I've been able to extract my proposed endian library from the sandbox, history and all. Here was the process: 1) Created a empty repository named "endian" in my GitHub account via the usual web interface. 2) From the command line, in a temporary directory: git svn clone https://svn.boost.org/svn/boost/sandbox/endian (Got a "Error validating server certificate...", and gave "p" as a response to the "(R)eject, accept (t)emporarily or accept (p)ermanently?" query. The process ran for perhaps 10 minutes, but that was fine because it was successful at recovering history. And it is a one-time process.) cd endian git branch -d git-svn git push --mirror git@github.com:Beman/endian.git That's it! The git branch command deletes the git-svn branch, which is an artifact of the conversion process. Finish off by cloning the library in its permanent local location: cd permanent-local-location git clone git@github.com:Beman/endian.git Comments? Is there a better way to do this? Once comments have come in, I'll create a doc page for doing this, with a link from the FAQ. --Beman

7 15

[intrusive] boost/intrusive/detail/has_member_function_callable_with.hpp: inheriting from a const class
by Krzysztof Czainski 20 Dec '12

20 Dec '12

Hello, I tried to use a boost::container::vector with a Texas Instruments compiler, and I got an error pointing to line 88 of <boost/intrusive/detail/has_member_function_callable_with.hpp> "Invalid base class", with Type=const std::allocator<something>" Here's the context: template <typename Type> class BOOST_PP_CAT(has_member_function_named_, BOOST_INTRUSIVE_HAS_MEMBER_FUNCTION_CALLABLE_WITH_FUNCNAME) { struct BaseMixin { void BOOST_INTRUSIVE_HAS_MEMBER_FUNCTION_CALLABLE_WITH_FUNCNAME(); }; struct Base : public Type, public BaseMixin { Base(); }; // <-- line 88 The problem seems to be the constness of Type. Here's a simplified example: struct X {}; template < class T > struct Y : T { Y() {} }; int main() { Y<const X> y; } The above example compiles fine with Linux gcc version 4.5.4, and MinGW 4.5.0, but fails with my TI compiler. My question is: is this a bug of the TI compiler, or is that compiler actually right about this, and should we fix this in Boost? For now, my workaround is: struct Base : public ::boost::remove_cv<Type>::type, public BaseMixin { Base(); }; // <-- line 88 Regards, Kris

3 4

[GIT] What happens to the Trac?
by John Maddock 20 Dec '12

20 Dec '12

Currently the issue tracker is somewhat nicely integrated with SVN, what are we doing for issue tracking short/medium/long term? Apologies if this has been covered already, John.

14 24

[release][thread] Permission to merge.
by Vicente J. Botet Escriba 19 Dec '12

19 Dec '12

Hi, I would like to merge this change [1][82094] It is related to this feature request [2](#7422 Provide a condition variable with zero-overhead performance penality), but we can consider it as a bug, as the performance were degraded since boost.1.45. After the change the performances have been improved consequently as showed in [3] trunk-ni-7422 in green respect to trunk-ni in orange. [1] https://svn.boost.org/trac/boost/changeset/82094 [2] https://svn.boost.org/trac/boost/ticket/7422 [3] https://docs.google.com/spreadsheet/ccc?key=0Ai_v0rSH1AXrdHl2RDN4UkFYNHZ2aX… Please, could I merge it after the regression test cycle? Best, Vicente

2 1

Should I use std::get or boost::get (or both) in Boost.Array
by Marshall Clow 19 Dec '12

19 Dec '12

I've got a feature request for Boost.Array to provide compile-time checked access to the members of an array. In C++11, this is done using std::get<Idx> (std::array). Fine, I can specialize this in Boost.Array - well, for C++11. I can't specialize a nonexistent template in namespace std for C++03 (well, I _can_ but the standard says I must not). But Boost.Tuple has a get<> template. I believe I can specialize that for Boost.Array, w/o stepping on Boost.Tuples code. What do people think? boost::get? std::get? Both? -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

2 4

Re: [boost] Heads up - string_ref landing
by Yanchenko Maxim 19 Dec '12

19 Dec '12

Marshall. low <mclow.lists. at> gmail.com> writes: > Please let me know what you think! As probably everyone, we have our own device for this. Here are some points and experience we gathered. 1. This class is essentially just an iterator_ range<char*> (modulo template for const/wchar_t), so it should either inherit from it or have corresponding converting ctors/operators. In this sense Olaf/Gennadiy's remarks are pretty valid. OTOH size is needed very frequently and having it precomputed is a good thing, so conversion approach seems to be better (but then we lose passing by reference as iterator_range, type_traits etc). I'm not sure what's more important. 2. Given the above, the name is misleading as it's not a reference to std::string. We use name char_range. 3. It's worth having a static constructor 'literal' (templated with size) to construct char_ranges from literals - as the compiler knows their size in compile time (minus zero terminator). It can be a constexpr too. Same manner - static function 'from_array', embrasing an array of chars in whole, assuming there is no zero terminator - useful for working with structures representing messages in char-based protocols with fixed-width fields. 4. (hack) We had to add a member function 'assign' (this is just operator=) to make boost::tokenizer return char_ranges. I don't like this part at all as it contradicts the meaning of say std::vector::assign, so I'd prefer another solution, probably in form of a customization point in boost::tokenizer. Thanks, Maxim

20 115

[Git] Boost website changes?
by Beman Dawes 18 Dec '12

18 Dec '12

The www.boost.org web site content needs to be reviewed, and all the Subversion references and instructions changed to Git and modular Boost. What is the best way to handle that? Create a branch similar to beta.boost.org? Who is willing to take on the management of updating web site content and monitor progress? --Beman

3 2

[Container] 'to_pointer' problem since 1.52
by Rich E 18 Dec '12

18 Dec '12

Just wanted to point out that there's an outstanding bug report due to some changes in Boost.Container that seem to have occured somewhere in the 1.52 dev cycle, reported here <https://svn.boost.org/trac/boost/ticket/7650>. In a nutshell, there is a compile time error caused by boost::container::list::const_iterator is trying to use a method called 'to_pointer' that doesn't exist (there is a 'pointer_to' method defined). We're using a modified version of boost/container/list.hpp at the moment, but it would be nice to ditch that come 1.53. The patch is so trivial that I thought it best to leave it up to the maintainer, as I really have no idea how to work with the current svn setup. cheers, Rich

2 1

Another set of macros to deprecate (and then remove)?
by Marshall Clow 18 Dec '12

18 Dec '12

There are a set of macros in Boost.config that describe "features that are not required by the C++ standard" Some of these features have been incorporated into C++11. I propose that we retire these macros, and have people use the shiny C++11 versions. In particular: BOOST_HAS_STATIC_ASSERT should be ! BOOST_NO_CXX11_ASSERT BOOST_HAS_VARIADIC_TMPL should be ! BOOST_NO_CXX11_VARIADIC_TEMPLATES BOOST_HAS_RVALUE_REFS should be ! BOOST_NO_CXX11_RVALUE_REFERENCES BOOST_HAS_CHAR_16_T should be ! BOOST_NO_CXX11_CHAR_16_T BOOST_HAS_CHAR_32_T should be ! BOOST_NO_CXX11_CHAR_32_T I'm using "!" here generically; in code you would replace #ifdef OLD_MACRO with #ifndef NEW_MACRO etc. I don't think this will be very disruptive; very few boost libraries use these macros. Opinions? Other macros that fit into this group? -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

8 12

compilation warning on HEAD
by Gaetano Mendola 18 Dec '12

18 Dec '12

The HEAD in trunk have some compilation warnings using gcc 4.7.2 the following will fix some of those. Another warning about unused result is in here: libs/serialization/src/basic_iarchive.cpp line 576, the value is used in a BOOST_ASSERT, I don't know how you manage those cases. Regards Gaetano Mendola Index: libs/serialization/src/basic_serializer_map.cpp =================================================================== --- libs/serialization/src/basic_serializer_map.cpp (revision 81900) +++ libs/serialization/src/basic_serializer_map.cpp (working copy) @@ -43,8 +43,7 @@ BOOST_ARCHIVE_DECL(bool) basic_serializer_map::insert(const basic_serializer * bs){ // attempt to insert serializer into it's map - const std::pair<map_type::iterator, bool> result = - m_map.insert(bs); + m_map.insert(bs); // the following is commented out - rather than being just // deleted as a reminder not to try this. Index: boost/archive/iterators/transform_width.hpp =================================================================== --- boost/archive/iterators/transform_width.hpp (revision 81900) +++ boost/archive/iterators/transform_width.hpp (working copy) @@ -112,6 +112,7 @@ transform_width(BOOST_PFTO_WRAPPER(T) start) : super_t(Base(BOOST_MAKE_PFTO_WRAPPER(static_cast< T >(start)))), m_buffer_out_full(false), + m_buffer_in(), m_remaining_bits(0), m_end_of_sequence(false) {} @@ -119,8 +120,8 @@ transform_width(const transform_width & rhs) : super_t(rhs.base_reference()), m_buffer_out_full(rhs.m_buffer_out_full), + m_buffer_in(rhs.m_buffer_in), m_remaining_bits(rhs.m_remaining_bits), - m_buffer_in(rhs.m_buffer_in), m_end_of_sequence(false) {} }; -- cpp-today.blogspot.it

4 4

[Git] Documentation for Git and Modular Boost conversion
by Beman Dawes 18 Dec '12

18 Dec '12

We are starting to pull together documentation for the Git and Modular Boost conversion. https://svn.boost.org/trac/boost/wiki/WikiStart#GitandModularBoost Comments and corrections welcome! I'm particularly interested in unanswered questions you have after reading these initial docs. --Beman

20 98

static_vector using aligned_storage
by Adam Wulkiewicz 18 Dec '12

18 Dec '12

Hi, I'm developing R-tree container for Boost.Geometry. To keep it short, there are containers of Values in leaf nodes. Those containers must have push_back() functionality. For static-size nodes I'm using a container based on boost::array. Unfortunately this means that default constructors of stored Values are called when the container is created. I'd like not to expect that Values have their default ctor implemented. I've implemented an alternative container using boost::aligned_storage. This is just a proof of concept. The code is available here: https://svn.boost.org/svn/boost/sandbox-branches/geometry/index/tests/stati… I've searched for this kind of container in Boost since I remember that someone proposed it some time ago but didn't find it anywhere. Is it released somewhere? Maby as a part of some library? If not, would you be so kind and see if my solution should work for any/most popular compiler/platform? I've tested it only on clang. To be specific, won't there be any problems with the memory aligmnent if I use this code for storage: boost::aligned_storage<sizeof(Value) * Capacity> m_storage; this for access: *(reinterpret_cast<Value*>(m_storage.address()) + i); and this for construction new (reinterpret_cast<Value*>(m_storage.address()) + i) Value(value); Regards, Adam

8 26

[range] Adapter to select class member
by Mark Snelling 17 Dec '12

17 Dec '12

Hi, I'm not sure if this has already been done but I have created a new Boost.Range adapter that will return a specified member variable of the class in the range, similar to the existing map_keys and map_values adapters. Would there be interest in this? For example consider the following code: #include <boost/range/adaptor/member.hpp> #include <boost/range/algorithm/copy.hpp> #include <boost/lexical_cast.hpp> #include <iostream> #include <vector> #include <string> struct A { int foo; std::string bar; }; int main(int argc, char* argv[]) { std::vector< A > input; for ( int i = 0; i < 10; ++i ) { A a; a.foo = i; a.bar = boost::lexical_cast< std::string >( i * 10 ); input.push_back( a ); } boost::copy( input | boost::adaptors::selected_member( &A::foo ), std::ostream_iterator< int >( std::cout, "," ) ); std::cout << std::endl; boost::copy( input | boost::adaptors::selected_member( &A::bar ), std::ostream_iterator< std::string >( std::cout, "," ) ); return 0; } Cheers, Mark

2 1

[crypto]not in https://github.com/boost-vault
by Jeff Flinn 16 Dec '12

16 Dec '12

It appears the crypto library that was in: http://www.boost-consulting.com/vault/index.php?action=downloadfile&filenam… Didn't get moved to https://github.com/boost-vault. Does anyone have access to the last vault incarnation? Thanks, Jeff

2 2

[release] permission to merge atomic and lockfree
by Tim Blechmann 16 Dec '12

16 Dec '12

hi all, apparently boost.atomic has been abandoned. i must admit, i'm very disappointed that the original author did hardly reacted neither on-list nor off-list. furthermore, it is blocking the release of boost.lockfree, so i'm volunteering to maintain this library. i'd rather see helge bahmann coming back and taking over responsibility for his code, but frankly, i lost all hopes that this is going to happen. iac, i'd like to get permission from the release managers to merge both atomic and lockfree to the release branch. thanks, tim

6 15

[GitHelp] Help desk support for developers moving to Git and modular Boost
by Beman Dawes 15 Dec '12

15 Dec '12

Documentation will aid developers moving to Git and modular Boost. See https://svn.boost.org/trac/boost/wiki/WikiStart#GitandModularBoost Beyond documentation, simply asking questions via a search engine works particularly well for Git. There is a vast amount of Git material available on the web, including some excellent YouTube videos. But documentation, web searches, and YouTube videos are not enough. Learning Git can be daunting - Git has more surface area than Subversion and it isn't obvious at first why some operations need to be done in a certain sequence or in a certain way or why they even need to be done at all. Two or three developers at C++Now mentioned that they became discouraged when they inadvertently got painted into a Git corner and couldn't find a way out. And even experienced git uses occasionally run into something they need human help with. This post proposes a virtual "Help Desk" to provide Boost specific answers to the inevitable questions that will come up during the transition to Git and modular Boost. The idea is that postings with at [GitHelp] subject tag will signal a request for help wrt Git or modular Boost. Anyone who can help should jump right in with a response. Comments? Suggestions? --Beman

3 2

[graph] A* search applied to knight's tour
by Dave Abrahams 15 Dec '12

15 Dec '12

Hi, I was just trying to work up an example for a class I'm teaching, to illustrate implicit graphs. The following shows how far I've gotten: https://gist.github.com/4153918 This is attempting to apply Warnsdorff's heuristic (choose the next move with the least out-degree) using A* search. I'm running into several problems having to do with the requirements of astar_search_no_init. In particular, the requirement that we can assign an index to every vertex is quite painful, since enumerating all the possible vertices in the search space is difficult. Any advice here? I suppose I could keep a real map and simply assign indices in the order vertices are encountered, but that seems pretty ugly to me. Any hints? -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost

2 4

Deadline extension: C++ Now 2013, Call for Submissions
by Hartmut Kaiser 15 Dec '12

15 Dec '12

Please see below for the extended deadline. ---------------------------------------------------------------------------- C++ NOW CONFERENCE 2013 - Aspen CO, USA, May 13-17, 2013, www.cppnow.org ---------------------------------------------------------------------------- CALL FOR SUBMISSIONS -------------------- We invite you to submit session proposals to the 2nd annual C++ Now Conference (Aspen CO, USA, May 13-17, 2013). Building upon the resounding success of C++ Now 2012 and five years of BoostCon, C++ Now 2013 will present leading speakers from the whole C++ community. The C++ Now Conference is dedicated to discussion and education about C++, an open and free language and standard. Our Conference will focus on discussion and education about open source software usage and developments in the C++ developer and user community. To reflect the breadth of the C++ and Boost communities, the conference includes sessions aimed at three constituencies: C++ and Boost end-users, hard-core Boost library and tool developers, and researchers pushing the boundaries of computation. The program fosters interaction and engagement within and across those groups, with an emphasis on hands-on, participatory sessions. As a multi-paradigm language, C++ is a melting pot where the most compelling ideas from other programming communities are blended in powerful ways. Historically, some of the most popular sessions at C++ Now have highlighted these concepts, from DSLs to functional programming to transactional memory and more. Bring your C#, Python, Ruby or Haskell influences to bear in an environment that will broaden their exposure. At C++ Now 2013 we would like to focus on parallel and distributed computing with C++. However, by no means this is intended to restrict the topics of proposals we hope to see. Any other topic related to C++ as outlined below is perfectly fine for submission. IMPORTANT DATES --------------- New proposal submissions due: January 5th, 2013. Proposals decisions sent (tentative program available): January 30th, 2013. Fully scheduled program available: February 24th, 2013. BEST PRESENTATION AWARDS ------------------------ We know how much effort it takes to prepare talks for our conference. For this reason we will award the best presentations in the following categories: Best Presentation, Best Short Presentation, Best Tutorial, and Best Workshop. The awards will be given based on the audience's voting. Each award will include the author's name listed on the cover of the C++ Now website for that year and a plaque containing all the C++ Now conference information. SESSION TOPICS -------------- Topics of interest include, but are not restricted to, the following: * Parallelism in the new C++11 standard * Parallel, distributed and GPGPU topics relating to C++ * C++11 and how it changes life for users and library writers * General tutorial sessions on C++11, the C++11 Standards library, and one or more Boost libraries * In-depth sessions on using specific Boost libraries * Case studies on using Boost * Experts panels * Advanced sessions on implementation techniques used within Boost libraries * Development workshops to extend or enhance existing Boost libraries * Workshops on design process * Infrastructure workshops such as Build tools, Website, Testing * Concepts and Generic Programming * Hardware and infrastructure presentations focused on how libraries can make better use of the technology * Software development tools and their application to C++ and or Boost * Other topics likely to be of great interest to C++ users and developers Interactive and collaborative sessions are encouraged, as this is the style of learning and participation that has proven most successful at such events. Sessions can be tutorial based, with an emphasis on interaction and participant involvement, or workshop based, whether hands-on programming or paper-based, discussion-driven collaborative work. SESSION FORMATS --------------- Presentations Presentations focus on a practitioner's ideas and experience with anything relevant to C++11, Boost and users. Panels Panels feature three or four people presenting their ideas and experiences relating to C++11 and Boost's relevant, controversial, emerging, or unresolved issues. Panels may be conducted in several ways, such as comparative, analytic, or historic. Tutorials Tutorials are sessions at which instructors teach conference participants specific skills relevant to C++11 and Boost. Workshops Workshops provide an active arena for advancements in Boost-relevant topics. Workshops provide the opportunity for experienced practitioners to develop new ideas about a topic of common interest and experience. Author's Corner Presentations These were introduced at BoostCon 2008, and were a great success. They are short (30 minute) sessions, focusing on tips on usage and design. In addition, we're looking to uncover the hidden design gems in Boost libraries. Tool Vendors Presentations We actively encourage tool vendors and ISP's to submit proposals for a special Tool Vendors Session Track aimed at products related to Boost and C++ (compilers, libraries, tools, etc.). Other formats may also be of interest. Don't hold back a proposal just because it doesn't fit into a pigeonhole. SUBMITTING A PROPOSAL --------------------- Standard Sessions are 90 minutes. You may submit a proposal for fractions Or multiples of 90-minutes. Fractional proposals will be grouped into 90 Minute sessions covering related topics. Longer sessions, such as tutorials and classes, will be assigned three hour (i.e. half day), or six hour (i.e. full day) time slots. Please include: * The working title. * Type of session: presentation, panel, tutorial, workshop, authors corner, vendor track, other. * A paragraph or two describing the topic covered, suitable for the conference web site. * Proposed length: 10-20 minute short talks, 45 minutes, 90 minutes, half day, full day. * Alternate lengths, if you are willing to make adjustments: 10-20 minute short-talks, 45 minutes, 90 minutes, half-day, full day. * Audience: users, developers, both. * Level: basic, intermediate, advanced. * A biography, suitable for the conference web site. * Your contact information (will not be made public). SUBMISSION DETAILS ------------------ All submissions should be made through the EasyChair conference management system: http://www.easychair.org/conferences/?conf=cppnow2013. If you have not already registered at EasyChair, you will need to do so in order to submit your proposal. All submissions will go through a peer review process. Authors are invited (but are not required) to submit PDF versions of full papers of up to 10 pages in ACM conference proceedings format (see http://www.acm.org/sigs/publications/proceedings-templates) The full papers are not required unless you want them published in the proceedings. All accepted proposals will be made available in the Association for Computing Machinery (ACM) Digital Library (approval pending). Best papers, after further reviews, will be considered to be book chapters or journal articles in a renowned journal. The session materials go on the C++ Now website and will be available to attendees. For general information on the C++ Now 2013 paper submission or the scope of technical papers solicited; please refer to the conference website at www.cppnow.org. For any other questions about the submission process or paper format, please contact the Program Committee at cppnow2013(a)easychair.com. If you have any technical problems with EasyChair, please contact EasyChair for help. Note: Presenters must agree to grant a non-exclusive perpetual license to publish submitted materials, either electronically or in print, in any media related to C++ Now. Hartmut Kaiser, email: hartmut.kaiser(a)gmail.com (Program Committee Chair) Dave Abrahams, email: dave(a)boostpro.com (Conference Chair) On behalf of the conference organizers

1 0

[system] Add noexcept to conform with C++11
by Vicente J. Botet Escriba 14 Dec '12

14 Dec '12

Hi, any news on https://svn.boost.org/trac/boost/ticket/7278. I could add them if you don't have the time now. Best, Vicente

6 18

[test] Getting an execution monitor to ignore a failed child processes
by Daniel James 14 Dec '12

14 Dec '12

Hi, A couple of days ago the inspect report was failing on the release branch and not the trunk branch (not currently, because I reverted the change which caused it). It turns out that this happened because inspect uses the program execution monitor. Inspect runs subversion to get the version information, but I wasn't running it in a subversion checkout, so the child process fails, which causes a signal which the execution monitor detects, throwing an exception. I guess it's thrown from the top level, so I can't catch it. I've got a patch ready which fixes this by running subversion from inside a nested execution monitor so that the exception is thrown at a more appropriate location. But this is a bit verbose, is there a better way to handle this? Perhaps temporarily stop the program execution monitor from handling failed process signals? I don't want to disable it for the rest of the program. Secondly, this doesn't happen on trunk. It looks like the program execution monitor isn't detecting the failure. This might be a bug in the new version. thanks, Daniel

1 0

[Proposal] Adding CPUID Library in Boost
by Shakti Misra 14 Dec '12

14 Dec '12

Hi All, Any interest in a cross platform CPU ID library? For a application I wanted to get the CPUID mostly to check the SSE2 status. So I missed it in Boost. So any interest for it? I am currently evaluating the library http://libcpuid.sourceforge.net/ This has a permissive license that I think can go with the Boost license. I mailed the author also, although he does not use boost, he told he can give any fixes or support needed. ~Thanks smisra

7 19

[odeint] Regression tests fail for unknown reason
by Karsten Ahnert 14 Dec '12

14 Dec '12

On some machines all of odeints regression tests in the release branch fail for an unknown reason (http://www.boost.org/development/tests/release/developer/numeric-odeint.html) Does anyone know what happens here?

4 4

Re: [boost] [Boost-testing] [odeint] Regression tests fail for unknown reason
by Vicente J. Botet Escriba 14 Dec '12

14 Dec '12

Le 13/12/12 21:40, Vicente J. Botet Escriba a écrit : > Le 13/12/12 21:28, Daniel James a écrit : >> On 13 December 2012 20:21, Vicente J. Botet Escriba >> <vicente.botet(a)wanadoo.fr> wrote: >>> Maybe, but I don't think so. All the Boost.Thread test are failling, and >>> most of them don't use Boost.Test. >>> The problem is that here is no information. What is happening with the >>> regression test results? >> I tried it on my machine: >> >> darwin.compile.c++ >> ../../../bin.v2/libs/thread/build/darwin-4.7x/debug/link-static/threading-multi/pthread/thread.o >> ../../../libs/thread/src/pthread/thread.cpp: In member function 'bool >> boost::thread::joinable() const': >> ../../../libs/thread/src/pthread/thread.cpp:398:34: error: cannot >> convert 'boost::detail::thread_data_ptr {aka >> boost::shared_ptr<boost::detail::thread_data_base>}' to 'bool' in >> return >> ../../../libs/thread/src/pthread/thread.cpp:399:5: warning: control >> reaches end of non-void function [-Wreturn-type] >> >> So it's shared_ptr's explicit bool? >> > Yes. I need to merge from trunk. I believed that I did it already :( > 06:01 Changeset /[81788]/ by viboes > <https://svn.boost.org/trac/boost/changeset/81788> > > Thread: fix shared_ptr implicit conversion to bool introduced in > [81780] <https://svn.boost.org/trac/boost/changeset/81780> > > I will take care also of the merge of Boost.Test > > 06:43 Changeset /[81791]/ by viboes > <https://svn.boost.org/trac/boost/changeset/81791> > Test: fix shared_ptr implicit conversion to bool introduced in > [81780] <https://svn.boost.org/trac/boost/changeset/81780> > why we are not able to see the comile errors on the regression test results? Vicente

2 2

Boost.Process: Formal review request
by Boris Schaeling 14 Dec '12

14 Dec '12

I'd like to ask for a formal review of the library which is known as Boost.Process 0.5: - Docs: http://www.highscore.de/boost/process0.5/ - Code: http://www.highscore.de/boost/process0.5/process.zip Since 2006 a lot of people spent a tremendous amount of work on a process management library for Boost. Since then Boost.Process went through two GSoC projects, had a formal review in 2011 where it got rejected, was discussed at BoostCon, went through a complete overhaul afterwards, spun off boost::asio::windows::object_handle and got a sponsorship. In fact the library is around for so long and has attracted so much interest that it could be called a de facto Boost library. People call it Boost.Process, and there are some who use the library in their projects. The main reason why Boost.Process is under construction for six years: Differences between the supported platforms Windows and POSIX. There are other libraries like Boost.Asio or Boost.Interprocess which have to deal with platform differences, too. But in their case no core functionality is affected. Classes like boost::asio::posix::stream_descriptor or boost::interprocess::windows_shared_memory are nice to have, and no one is worried that they only work on one platform. Boost.Process has to deal with platform differences in core functions. For example, resource leaking is unacceptable (zombie processes on POSIX and open HANDLEs on Windows when child processes exit). Given that platforms are very different two extreme solutions are possible: Abstract away differences at all costs. Or tell the library user to call platform-specific system functions. As none is satisfactory, a balance between these extremes has to be found. But where this balance should be exactly can be discussed with no end. Someone has to make a decision at some point, and that will be another important role for the review manager. :) Looking back at what has been accomplished since the first review, I think Boost.Process 0.5 is a huge step forward: * The library is now fully customizable. While previous versions had a function called launch() which was immutable, the current version is based on things called executors and initializers. An executor is basically a struct with member variables which will be passed as arguments to a system function to spawn a child. Initializers set those member variables. Library users pick initializers provided by Boost.Process or define their own to setup executors. * Boost.Process 0.5 is cleaner and more focused as it makes better use of other Boost libraries. For example, previous versions had their own stream classes. They were removed in the current version - Boost.Iostreams is used instead. Now Boost.Process doesn't reinvent concepts or reimplement functions anymore which belong in other libraries. All of that makes me believe it's time for a new review. Boris

5 9

[Interprocess] Experimental Win32 Mutexes
by Brink, Robert (GE Aviation, US) 13 Dec '12

13 Dec '12

I'm running Boost 1.52 on Windows 7, Visual Studio 2010. I noticed in sync\interprocess_mutex.hpp there is a windows mutex implementation that is hidden behind the BOOST_INTERPROCESS_FORCE_GENERIC_EMULATION macro. The comment indicates that it is "Experimental". Could someone shed some light on what is Experimental about it and what the general plans for this feature are? I was having a problem with many processes all spin-locking when allocating shared memory that I traced down to the old mutex implementation for shared memory. I enabled the experimental feature in my local build ( by commenting out the above macro in the detail\workaround.hpp file) and it seems to fix my problems. My performance is much improved. But what are my risks for using this implementation? I'm a little nervous to depend on something marked as "Experimental". Thanks Rob Brink

3 5

[Interprocess] Managed mapped file questions
by Jorge Lodos Vigil 13 Dec '12

13 Dec '12

Hi First of all, thank you for boost interprocess :-) I have a couple of questions: 1. When you grow a managed mapped file, the current implementation fills all the new space with zeroes. This is less efficient than just resizing the file. The comments in the code implies there is a reason, so what is it? 2. When the size to map is too small, take 1 or 2 bytes for instance, the library fails in a non elegant way. This is a corner case, but I could not find this documented. Is this a bug? I'm asking this before sending any sample code or creating tickets, but of course I could do that as well if there is the need. Thanks again. Cheers Jorge

2 4

[Container][Move] #if defined(BOOST_MOVE_USE_STANDARD_LIBRARY_MOVE): boost::move_backward is undefined
by Hartmut Kaiser 13 Dec '12

13 Dec '12

Hey, If BOOST_MOVE_USE_STANDARD_LIBRARY_MOVE is defined, then compiling Boost.Container fails because its missing boost::move_backward. Patch is attached. Ok to commit? Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

2 3

Boost.Process 0.5: And another minor update
by Boris Schaeling 13 Dec '12

13 Dec '12

I've uploaded a new version of Boost.Process 0.5 to <http://www.highscore.de/boost/process0.5/>: - First command line argument passed to set_args is used as a path to the executable to start - No escaping of command line arguments anymore with set_args (see <http://article.gmane.org/gmane.comp.lib.boost.devel/236137>) - Updated documentation Boris

4 6

Use of deprecated macros in Boost
by Marshall Clow 13 Dec '12

13 Dec '12

In Boost 1.50, we (Boost) marked a bunch of macros as "deprecated" In Boost 1.51, we deprecated a bunch more - replaced them with new, shiny macros. I've been working with many of you (library maintainers) to remove all the uses of deprecated macros in Boost, and we've been almost completely successful .. on the trunk. We're a week away from the freezing of the release branch for the 1.53 release, and I'd like to make sure that all those macro changes get merged over to the release branch. http://www.boost.org/development/ I will be happy to help - just let me know. Thanks in advance! -- Marshall

3 11

Heads up - string_ref landing
by Marshall Clow 12 Dec '12

12 Dec '12

I'm about to check in some new functionality into the string_algo library; an implementation of string_ref. A string_ref is a non-owning reference to a string. It is implemented as a {pointer, length} pair, and is exceedingly useful when parsing, and manipulating strings in "read-only" ways. The header will be in boost/algorithm/string_ref.hpp, but I welcome discussion about where it should live. Ideally, I think it should be just "boost/string_ref.hpp". Basic sanity tests will be checked in with the header file - I have tested on clang, clang11, and gcc. One reason for checking this in now is to get the tests run on lots of different systems. Docs will be coming soon, but http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3442.html is the proposal for "a future version of C++" ;-) Please let me know what you think! -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

18 45

[smart_ptr][thread][test] breaking change on shared_ptr operator bool.
by Vicente J. Botet Escriba 12 Dec '12

12 Dec '12

Hi, https://svn.boost.org/trac/boost/changeset/81780 " Use explicit operator bool when available; ..." introduces a breaking change on shared_ptr in Boost.Thread and Boost.Test at least. I would preferred if this breaking change was announced and why not added conditionally so that the user could move smoothly to the new semantic. Anyway, I wanted to make this evident so that the Boost maintainer using this facility fixes their code as soon as possible. Best, Vicente

7 19

[atomic] Header rearrangement
by Andrey Semashev 12 Dec '12

12 Dec '12

Hi, Before merging Boost.Atomic to release I would like to propose to rearrange library headers a bit: 1. The current boost/atomic/config.hpp and platform.hpp seem to be not intended for public use as they don't provide any public components. I propose to move them to boost/atomic/detail. 2. The boost/atomic.hpp header defines the atomic<> template. I propose to move its contents to boost/atomic/atomic.hpp. The boost/atomic.hpp will be left as the "include all" header and will only include boost/atomic/atomic.hpp for now. The motivation for the proposal is to cleanup the public library interface (header layout) and simplify extension later. For instance, function-style interface can be added as a new header in boost/atomic, it would fit naturally in the proposed layout. Also, with the upcoming transition to git it seems that all library headers should reside in the library's own subdirectory and not directly in boost/. AFAICT, the change will not affect any other libraries since only boost/atomic.hpp is included currently. If noone objects (Tim, I would very much like to hear from you on this), I can do the necessary changes.

3 2

[thread 1.48] Multiple interrupt/timed_join leads to deadlock
by Gaetano Mendola 12 Dec '12

12 Dec '12

Hi all, I was investigating a rare deadlock when issuing an interrupt and a timed_join in parallel. I come out with the the following code showing the behavior. This is the backtrace of it: http://pastebin.com/xArHgHXf The deadlock is rare so sometime you need to wait a bit. I couldn't try it with boost 1.52 because the code is invalid due the precondition of "thread joinable" when issuing the timed_join. Is the code not valid or a real bug? Regards Gaetano Mendola ////////////////////// CODE ////////////////////// #include <iostream> #include <boost/thread.hpp> struct Runner { void operator()() { const boost::posix_time::time_duration mySeconds = boost::posix_time::seconds(100); boost::this_thread::sleep(mySeconds); } }; struct Interrupter { Interrupter(boost::thread& aThread, boost::barrier& aBarrier) : theThread(aThread), theSeconds(boost::posix_time::seconds(1)), theBarrier(aBarrier) { } void operator()() { theBarrier.wait(); for (int i=0; i<1000;++i) { theThread.interrupt(); theThread.timed_join(theSeconds); } } boost::thread& theThread; boost::posix_time::time_duration theSeconds; boost::barrier& theBarrier; }; int main() { for (size_t i = 0; i < 1000000; ++i) { Runner myRunner; boost::thread myRunnerThread(myRunner); boost::barrier myBarrier(2); Interrupter myInterrupter1(myRunnerThread, myBarrier); Interrupter myInterrupter2(myRunnerThread, myBarrier); boost::thread myInterrupterThread1(myInterrupter1); boost::thread myInterrupterThread2(myInterrupter2); myInterrupterThread1.join(); myInterrupterThread2.join(); myRunnerThread.join(); std::cout << "."; std::cout.flush(); } }

5 34

[thread] [Boost-testing] Trunk regression failed on missing 'virtual_noexcept.cpp'
by Rene Rivera 11 Dec '12

11 Dec '12

Seems the thread lib has some missing test files? ---------- Forwarded message ---------- From: Jim Bell <Jim(a)jc-bell.com> Date: Tue, Dec 11, 2012 at 10:37 AM Subject: [Boost-testing] Trunk regression failed on missing 'virtual_noexcept.cpp' To: Running Boost regression tests <boost-testing(a)lists.boost.org> error: at G:/boost/GCC/trunk/tools_bb/**kernel\modules.jam:107 error: Unable to find file or target named error: 'virtual_noexcept.cpp' error: referred to from project at error: '../libs/thread/test' ______________________________**_________________ Boost-Testing mailing list Boost-Testing(a)lists.boost.org http://lists.boost.org/**mailman/listinfo.cgi/boost-**testing<http://lists.boost.org/mailman/listinfo.cgi/boost-testing> -- -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim - grafikrobot/yahoo

2 1

Request for interest in a library to ease double dispatching
by Per Karlström 11 Dec '12

11 Dec '12

Hi, I have been tinkering on a template library to ease the use of double dispatching. Now I know there are other techniques such as visitor patterns that might solve this problem in a more general way. However I believe that there are occasions when using double dispatch is a good way forward. I have some excerpts of example code at the end of this mail. Of course if I somehow have missed a boost library that already handles this I would be happy to know about it. So if there is even any interest for this I would be happy if someone would like to cooperate with me to make this library better and in the end so good so that it can be part of boost. I feel I do not have the time to spare to finalize this on my own, plus I feel I still have things to learn and would be happy to cooperate with someone more experienced in template programming. What I in that case need help with is: *How (or is it) possible to make the library more transparent to the number of types that should be in the double dispatch hierarchy. Right now, as I have shown in the code at the end of this mail, you have to put a post-fix number telling how many types to use. *How (if possible) can a class be double dispatchable with different return types. The way I solved it was with a union. But would it somehow be possible to do like this struct Val : public DoubleDispatchable<bool,A,B>, public DoubleDispatchable<int,A,B> *What else would be needed to start the journey to make this a library fit for boost (is it even good enough to ever make into boost?) If anyone is interested in a cooperation I am happy to provide my working draft of this library and to have a more private talk about how we could move forward. Best Regards Per Karlström For now a union is used to hold the return value to make this simmilar for all types of returns. union ReturnVal { float float_type_m; bool bool_type_m; ReturnVal(const bool& bool_type_):bool_type_m(bool_type_){} ReturnVal(const float& float_type_):float_type_m(float_type_){} ReturnVal():bool_type_m(false){} }; In essence a library user can define handler classes akin to this: struct less : public DoubleDispatchHandler_3<ReturnVal,A,B,C> { return_type handle_alpha_alpha(const alpha_type& arg1, const alpha_type& arg2) const {return arg1 < arg2} return_type handle_alpha_beta (const alpha_type& arg1, const beta_type& arg2) const {return true;} return_type handle_alpha_gamma (const alpha_type& arg1, const gamma_type& arg2) const {return true;} //And all other combinations }; Or with a default function struct equal : public DoubleDispatchHandler_3<ReturnVal,A,B,C> { return_type handle_default() const {return false;} return_type handle_alpha_alpha(const alpha_type& arg1, const alpha_type& arg2) const; return_type handle_beta_beta (const beta_type& arg1, const beta_type& arg2) const; return_type handle_gamma_gamma (const gamma_type& arg1, const gamma_type& arg2) const; }; Then the base class is derived from DoubleDispatchable class Val : public DoubleDispatchable_3<ReturnVal,A,B,C> { public: virtual ~Val(){} virtual std::ostream& print(std::ostream& ost) const=0; virtual bool operator<(const Val& other) const =0; virtual bool operator==(const Val& other) const =0; virtual float combine(const Val& other) const =0; }; While Child classes had to define the member function dispatch_<type> struct A : public Val { int val_m; private: //Handles the first double dispatch call return_type dispatch_alpha(const alpha_type& alpha, const handler_type& handler) const { return double_dispatch(alpha,*this,handler); } return_type dispatch_beta(const beta_type& beta, const handler_type& handler) const { return double_dispatch(beta,*this,handler); } return_type dispatch_gamma(const gamma_type& gamma, const handler_type& handler) const { return double_dispatch(gamma,*this,handler); } public: A(const int& val_=0):val_m(val_){} //Normal calls to the operators via a template function bool operator<(const Val& other) const { return double_dispatch(*this,other,less()).bool_type_m; } bool operator==(const Val& other) const { return double_dispatch(*this,other,equal()).bool_type_m; } float combine(const Val& other) const { return double_dispatch(*this,other,add()).float_type_m; } std::ostream& print(std::ostream& ost) const { ost<<"A("<<val_m<<")"; return ost; } }; class B{...}; class C{...};

3 5

Registration for C++Now 2013 is now open
by Boris Kolpackov 11 Dec '12

11 Dec '12

The seventh annual C++Now Conference (formerly BoostCon) will be held at the Aspen Center for Physics in Aspen, Colorado, May 12th to 17th, 2013. "We are thrilled to announce the second annual C++Now conference, the whole-language edition of BoostCon covering all the coolest topics in C++," said Dave Abrahams, Conference Co-Chair. "In 2012, we broadened the conference scope by adding a third track and offering more C++11 coverage than any other event, and the community responded with an unprecedented number of registrations. In 2013, we are going to build on that success with foundational sessions integrating what we've all learned about using C++11 during the past year, while continuing the exploration of cutting-edge topics that BoostCon attendees have come to expect." Early Bird Savings Deadlines! Early Bird conference registration, which ends April 14th, 2013, costs $599. After that date, the registration fee is $699. Register now at our registration page <http://www.eventbrite.com/event/2717332615>. Early Bird hotel registration ends December 31st, 2012 and saves $20 per night. Please reserve your room using the Aspen Meadows online reservation system <https://resweb.passkey.com/go/cplusplusnow2013> Speakers If you are interested in presenting, we are currently accepting proposals <http://cppnow.org/2013-call-for-submissions/>. Registration fee is waived for one speaker of every standard session presentation. Shorter sessions are prorated. Student/Volunteers Registration fees will be waived for a limited number of individuals that wish to attend as volunteers. Volunteer work consists of helping to run the conference and will not prevent volunteers from attending sessions. This is the first year this opportunity is being offered. If you are interested in applying to attend as a volunteer, contact us at <organizers(a)cppnow.org>. Sponsors For a copy of the conference Sponsorship Prospectus contact sponsorship(a)cppnow.org. C++Now is presented by Boost in-cooperation with ACM. Permanent link for this announcement is: http://cppnow.org/2013-registration-announcement/

1 0

Using c++11 features in clang
by Marshall Clow 10 Dec '12

10 Dec '12

In response to a some questions on the boost-users list (and boost bug reports), I wrote up this: http://marshall.calepin.co/llvmclang-and-standard-libraries-on-mac-os-x.html I don't know if this should be a FAQ entry for Boost, or for clang. Suggestions/comments/edits welcome. -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

3 3

[hash] Tests fail on Intel compiler
by Andrey Semashev 10 Dec '12

10 Dec '12

Hi, I've been looking through Boost.Atomic and Boost.Thread tests on the "lazy piranha fedora 17 64" tester, intel-linux-13.0.1 compiler. The tests fail because Boost.Thread does not compile because of Boost.Hash. Here's an example of build log: http://www.boost.org/development/tests/trunk/developer/output/lazy%20piranh… The problem is that apparently BOOST_HASH_CONFORMANT_FLOATS is not defined on this compiler while there are both ::fpclassify and std::fpclassify functions. Are there valid reasons for not defining the macro on this compiler?

2 1

[trac] Add new components
by Michel Morin 10 Dec '12

10 Dec '12

The following four libraries do not have "components" in trac (lockfree already has the component in trac): - atomic - coroutine - multiprecision - odeint (numeric/odeint) Regards, Michel

4 4

[algorithm][hex] function hex_char_to_int in unnamed namespace in header file
by Felipe Magno de Almeida 10 Dec '12

10 Dec '12

Hello, AFAIK, unnamed namespaces are dangerous in headers. There is a commentary just above the function definition: // this needs to be in an un-named namespace because it is not a template // and might get included in several compilation units. This could cause // multiple definition errors at link time. But it seems the better thing would be to define it inline. It is exactly because it can be used in several translation units that it can cause an ODR violation if defined in a unnamed namespace AFAIK. Regards, -- Felipe Magno de Almeida

3 8

Boost new library policy
by islam y. yasar 10 Dec '12

10 Dec '12

Hi Boost Developers; i and my friend want to develope a library for boost. Is there any policy document for that ? i want to learn this process step by step. thank you.

6 9

[boost::asio] SCTP support with boost::asio
by Ajay Yadav 10 Dec '12

10 Dec '12

Hi, I am newbie to the boost library. I would like to develop the SCTP client-server application. Is boost::asio supported SCTP. Please guide me how I can make the application using SCTP. Regards, Ajay Yadav DISCLAIMER: ----------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. It shall not attach any liability on the originator or NECHCL or its affiliates. Any views or opinions presented in this email are solely those of the author and may not necessarily reflect the opinions of NECHCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of the author of this e-mail is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. . -----------------------------------------------------------------------------------------------------------------------

2 1

[quickbook] template vs block vs phrase issues
by Andreas Pokorny 09 Dec '12

09 Dec '12

Hi, I use quickbook to write software design documentation targeting pdf. We now introduce a requirements tracking system that includes both source code and design documents. To describe or refer to requirements in docbook docments special xml markup is needed. I.e. something like <reqfooo><status>approved</status><version>1</version><id>DoOnlyNeededStuff</id><description></description></regfoo>. Since I do not want to write XML I added quickbook templates: [template reqfoo[id contents]'''<reqcfoo><id>'''[id]'''</id>'''[contents]'''</reqfoo>'''] [template sdesc[contents]'''<shortdesc>'''[contents]'''</shortdesc>'''] [template verification[contents]'''<verifycrit>'''[contents]'''</verifycrit>'''] [template source[contents]'''<source>'''[contents]'''</source>'''] [template usecase[contents]'''<usecase>'''[contents]'''</usecase>'''] [template status[contents]'''<status>'''[contents]'''</status>'''] [template version[contents]'''<version>'''[contents]'''</version>'''] and finally: [template desc[contents]'''<description>'''[contents] '''</description>'''] Now I want to use block elements inside the contents parameter of desc. Is there any way to achieve that? The only thing I can think of is: [template desc[]'''<description>'''] [template enddesc[]'''</description>'''] But then quickbook is just as good as xml! I tried to make desc a block level template by adding a line break at different positions, but then I get broken xml code, since para tags are spread around <description> regards Andreas

2 5

[Git] Modularizing Boost libraries with sublibs
by Daniel Pfeifer 09 Dec '12

09 Dec '12

While adding Boost.ODEint to the modularization manifest, I realized some inconsistencies about sublibs. The directories in "libs" usually contain one library each. In this case, we move the content to a dedicated Git repository. Some directories however (algorithm, numeric) host multiple libraries. How should we treat them? Move each one to a dedicated Git repository, or leave them grouped together? What's currently inconsistent, is that "numeric" is split into individual repositories, while "algorithm" is not. Further, I saw that the Git submodules of numeric's sublibraries are generated in "libs" rather than "libs/numeric", which is wrong. However, before I fix it, we need to decide whether these individual submodules should be individual or not. Opinions? Cheers, Daniel

4 5

Re: [boost] [Git] tools/wave missing (was: Documentation for Git and Modular Boost conversion)
by Hartmut Kaiser 09 Dec '12

09 Dec '12

> On Fri, Dec 7, 2012 at 3:42 PM, Eric Niebler <eric(a)boostpro.com> wrote: > > On 12/7/2012 11:44 AM, Oliver Kowalke wrote: > > >> Do I have to clone an additional submodule (which is not mentioned in > >> the docu)? > > > > Beman's docs appear to lack instructions for how to clone the > > super-project and initialize the sub-modules. That would be a nice > > addition. I don't know the steps and can't find them ATM, but I know > > it's documented *somewhere*. Beman? > > Just added: https://svn.boost.org/trac/boost/wiki/TryModBoost > > The original instructions were buried in a C++Now presentation slide. When I follow those steps as far as I can see everything looks fine except for tools/wave, which is missing. Is that intentional? Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu > > Thanks, > > --Beman > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

2 2

[Smart Pointers]
by Rahul Sr 09 Dec '12

09 Dec '12

Hi All, This is my first post though so please bear with my sentences. I have used scoped_ptr but this is too tied with new/delete semantics i.e. can't use it with pointers which gets allocated from specialized memory area. class AManager { public: A * allocate(); void deallocate(A * p); }; class A { ..... }; This specially happens when I use scoped pointer for C like pointers/allocator: Can I modify scoped pointer to have release semantics which is user defined: template<typename T> class DefaultReleasePolicy { static void releaseA(T * p) { delete p; } }; class ReleaseAPolicy { static void releaseA(A * p) { AManager::getInstance()->deallocate(p); } }; template<typename T,typemame ReleasePolicy = DefaultReleasePolicy<T> > class ScopedPtrModified { ~ScopedPtrModified() { ReleasePolicy::release(m_ptr); } }; Is this fine? Let me know your thoughts. Regards, Rahul

3 3

[odeint] Request to merge odeint into release branch
by Karsten Ahnert 09 Dec '12

09 Dec '12

I would like to ask for permission to merge odeint into the release branch. There are currently four failures in the regression tests. Two have already been fixed. The other two originate from the build time out of 180 seconds. These two tests will often require longer build times, since they heavily use Boost.Fusion, Boost.Units and Boost.MPL.

2 5

[multiprecision] Request permision to merge to release.
by John Maddock 09 Dec '12

09 Dec '12

I'd like to ask permission to merge the multiprecision lib to release. Note that as things stand I'm still chasing down test failures, but these are now mostly down to: * Things that work locally, but the testers haven't cycled yet. * 300s timeouts - mostly from the intel compiler :-( Aside: in an effort to reduce the number of timeouts, I've basically gutted some of the tests when the compiler is Intel, and I think I have all the build times under 20s on my Linux box, yet I'm still getting 300s timeouts on some tester machines, either those machines are seriously underpowered or I'm missing something here :-( Cheers, John.

3 5

[smart ptr] [shared] suggestion: single pointer in object returned from make_shared
by Julian Gonggrijp 09 Dec '12

09 Dec '12

Dear Smart Ptr maintainer(s), I recently learned that boost::make_shared allocates the space for the pointee and the reference counter in one go. It makes a lot of sense, and I might have suggested it if it wasn't already the case. Now I'm assuming that a shared_ptr stores two raw pointers internally, one to the pointee and one to the counter. I guess that would be necessary in the "normal" case where the pointee and the counter are allocated separately. Now in the case where the shared_ptr is created by make_shared, ideally you'd need to store only one raw pointer because pointee and counter reside in the same memory object. That would be the finishing touch to a nonintrusive smart pointer that really performs like an intrusive one. To me such a thing seems highly desirable. I realise this would require a new implementation of the shared pointer. Could this somehow be made to cooperate or at least coexist with the old shared_pointer? Would it perhaps even be an option to deprecate the old shared_pointer in order to entirely replace it by the new version in the future? I'll be most interested to read your comments on this idea. -Julian

1 0

Boost.Test updates in trunk: need for (mini) review?
by Gennadiy Rozenal 09 Dec '12

09 Dec '12

Hi, It's been a long while since I merged any changes into boost release and by now there are whole bunch of new features there. Some are small, but some others are big ones such that they can change the way people use the library. I'd like to list them here (excluding bug fixes and removal of deprecated interfaces) and ask what should we do with these. Specifically let me know if you think these require some kind of (mini) review from community, but any other comments are welcome as well. So here we go: I. New testing tool BOOST_CHECKA This tool is based on excellent idea from Kevlin Henney. I chose the name CHECKA for this tool due to the lack of better name, but I am open to suggestions. This testing tool capable of replacing whole bunch of existing other tools like BOOST_CHECK_EQUAL, BOOST_CHECK_GT etc. Usage is the most natural you can wish for: BOOST_CHECKA( var1 - var2 >= 12 ); And the output will include as much information as we can get: error: in "foo": check var1 - var2 >= 12 failed [23-15<12] II. New "data driven test case" subsystem New data driven test case subsystem represent a generalization of parameterized test case and test case template and eventually will replace both. The idea is to allow user to specify an arbitrary (monomorphic or polymorphic) set of samples and run a test case on each of the samples. Samples can have different arity, thus you can have test cases with multiple parameters of different types. For now we support following dataset kinds (aside of generators none of dataset constructions routines performs *any* copying): a) singleton - dataset constructed out of single sample data::make(10) - singleton dataset with integer sample data::make("qwerty") - singleton dataset with string sample b) array - dataset constructed out of C array int a[] = {1,2,3,4,5,6}; data::make(a) - dataset with 6 integer values c) collection - dataset constructed out of C++ forward iterable collection std::vector<double> v{1.2, 2.3, 3.4, 5.6 }; data::make(v) - dataset with 6 double values d) join - dataset constructed by joining 2 datasets of the same type int a[] = {1,2,3}; int b[] = {7,8,9}; data::make(a) + data::make(b) - dataset with 6 integer values e) zip - dataset constructed by zipping 2 datasets of the same size, but not necessarily the same type This dataset has an arity which is sum of argument dataset arities. int a[] = {1,2,3}; char* b[] = {"qwe", "asd", "zxc"}; data::make(a) ^ data::make(b) dataset with 3 samples which are pairs of int and char*. f) grid - dataset constructed by "multiplying" 2 datasets of the same different sizes and types type This dataset has an arity which is sum of argument dataset arities. int a[] = {1,2,3}; char* b[] = {"qwe", "asd"}; double c[] = {1.1, 2.2}; data::make(a) * data::make(b) * data::make(c) dataset with 12 samples which are tuples of int and char* and double. g) xrange generator dataset which produes samples in some range data::xrange( 0., 3., 0.4 ) - dataset with 8 double samples data::xrange<int>((data::begin=9, data::end=15)) - dataset with 6 int samples data::xrange( 1., 7.5 ) - dataset with 7 double samples data::xrange( 5, 0, -1 ) - dataset with 5 int samples h) random - generator dataset with unlimited number of random samples data::random(data::distribution = std::normal_distribution<>(5.,2)) dataset with random double numbers following specified distribution data::random(( data::engine = std::minstd_rand(), data::distribution = std::discrete_distribution<>(), data::seed = 20UL )); dataset with random int numbers following specified distribution While all this interfaces can be used by itself to build complex datasets with various purposes, primary use case it was developped for is new data driven test case interface: BOOST_DATA_TEST_CASE( test_name, dataset, parameter_names... ) Here are couple examples: int samples1[] = {1,2,3}; BOOST_DATA_TEST_CASE( t1, samples1, sample ) { BOOST_CHECKA( foo(sample) > 0 ); } Above test case is going to be executed 3 times with different sample values char* strs[] = {"qwe", "asd", "zxc", "mkl" }; BOOST_DATA_TEST_CASE( t1, data::xrange(4) ^ strs ^ data::random(), intval, str, dblval ) { MyObj obj( dblval, str ); BOOST_CHECKA( obj.goo() == intval ); } Above test case will be executed 4 times with different values of parameters intval, str, and dblval. Polymorphic datasets are still being developed, but should appear soon(ish). III. Auto-registered test unit decorators. Previously is was not possible and/or convenient to assign attributes to the automatically registered test units. To alleviate this I've introduced a notion of test unit decorator. These can be "attached" to any test unit similarly to like it is done in other languages Following decorators already implemented: label - adds labels to a test unit expected_failures - set expected failures for a test unit timeout - sets timeout for a test unit description - sets a test unit description depends_on - sets a test unit dependency enable_if/disable_if - facilitates a test unit status change fixture - assigns fixture to a test units Test unit description is new test unit attribute, which is reported by new list_content command line argument described below. Usage of labels covered below as well. enable_if/disable_if allow new, much more flexible test management. By adding enable_if/disable_if decorators to the test unit you can conditionally select which test units to run at construction time based on some compile time or run-time parameters. And we finally we have suite level fixtures which are set by attaching fixture decorator to a test suite (suite level fixtures executed once per test suite). Attachment of decorator is facilitated by using of BOOST_TEST_DECORATOR. Note that you can use any of '+', '-', '*' symbols to attach decorator (and any number of '*'): BOOST_TEST_DECORATOR( + unittest::fixture<suite_fixture>() ) BOOST_AUTO_TEST_SUITE( my_suite1 ) { } BOOST_TEST_DECORATOR( - unittest::timeout( 100 ) - unittest::expected_failures( 1 ) - unittest::enable_if( 100 < 50 ) ) BOOST_AUTO_TEST_CASE( my_test5 ) BOOST_TEST_DECORATOR( **** unittest::label( "L3" ) **** unittest::description( "suite description" ) **** unittest::depends_on( "my_suite2/my_test7" ) ) BOOST_AUTO_TEST_CASE( my_test11 ) IV Support for "run by label" plus more improvements for filtered runs Previously you only had an ability to filter test unit to execute by name. Now you can attach labels to test units and create collections to run which are located in arbitrary positions in test tree. For example you can have special label for performance test cases, which is attached to all test units which are responsible for testing performance of your various components. Or you might want to collect exception safety tests etc. To filter test units by level you still use --run_test CLA. Labels are dented by @prefix: test.exe --run=@performance You can now repeat --run_test argument to specify multiple conditions: test.exe --run=@performance,@exception_safety --run=prod/subsystem2 In addition run by name/label now recognizes dependencies. So if test unit A depends on test unit B and test unit B is disabled/is not part of current run test unit A will not run as well. Finally you now have an ability to specify "negative" conditions, by prefixing name or label with ! test.exe --run=!@performance This will run all test units which are not labeled with "performance". V. Support for failure context In many scenarios it is desirable to specify an additional information to a failure, but you do not need to see it if run is successful. Thus using regular print statements is undesirable. This becomes especially important when you develop common routine, which performs your testing and invoke it from multiple test units. In this case failure location is no help at all. To alleviate this problem two new tools are introduced: BOOST_TEST_INFO BOOST_TEST_CONTEXT BOOST_TEST_INFO attaches context to next assertion which is executed. For example: BOOST_TEST_INFO( "a=" << a ); BOOST_CHECKA( foo(a) == 0 ); BOOST_CHECK_CONTEXT attaches context to all assertions within a scope: BOOST_CHECK_CONTEXT( "Starting test foo from subset " << ss ) { BOOST_CHECKA( foo(ss, a) == 1 ); BOOST_CHECKA( foo(ss, b) == 2 ); } VI. Two new command line arguments: list_context, wait_for_debugger Using list_context you can see a full or partial test tree of your test module. wait_for_debugger allows to force test module to wait till you attach debugger. VII. Colored output. Using new CLA --color_output you can turn on colored output for error and information messages VIII New production testing tools interface introduced This feature was covered in details in my presentation in BoostCon 2010. The gist if this is an ability to use Boost.Test testing tools interfaces in production (nothing to do with testing) code. User supplied implementation is plugged in IX. Number of smaller improvements: * Notion of framework shutdown. Allows to eliminate some fake memory leaks * Added checkpoints at fixture entry points, test case entry point and test case exit point for auto registered test cases * New FPE portable interfaces introduced and FPE handling is separated from system errors handling. You can detect FPE even if catch_system_error is false * Added an ability to erase registered exception translator * execution_monitor: new interface vexecute - to be used to monitor nullary functions with no result values * test_tree_visitor interface extended to facilitate visitors applying the same action to all test units * execution_monitor use typeid to report "real" exception type if possible. * New ability to redirect leaks report into a file Thank you for your time, Gennadiy

21 66

[config] Macro for null pointer
by Edward Diener 08 Dec '12

08 Dec '12

I have found something like this to be helpful, when working with multiple compilers: #include <boost/config.hpp> #if defined(BOOST_NO_NULLPTR) #define BOOST_XXX_NULLPTR 0 #else #define BOOST_XXX_NULLPTR nullptr #endif where XXX is some local name for my own use. And then use BOOST_XXX_NULLPTR in places where a null pointer is needed. Would this be a candidate for a BOOST_NULLPTR macro in the config library instead ? Edward Diener

16 63

Re: [boost] [boost-steering] Re: [Git] Documentation for Git and Modular Boost conversion
by Brian Wood 08 Dec '12

08 Dec '12

Dave Abrahams: > Boost is making this transition. It *will* cause some disruption. It > will also make things easier for some people. I'm glad to hear this effort is continuing. > IMO we should not burden this move, which is supposed to > make it easier and more efficient overall for Boost to operate, > with any unnecessary obligations. That sounds harsh, but I guess that's the way the cookie crumbles. -- Brian Wood Ebenezer Enterprises -- so far G-d has helped us. http://webEbenezer.net

1 0

[serialization] Proposal: make 'version' trait (and others) enable_if-friendly
by Gabriel Redner 07 Dec '12

07 Dec '12

I have recently run up against a limitation of the serialization library in terms of specializing the 'version' trait. Fortunately, I believe the issue has a simple workaround which I don't believe will break existing code. In general, one can change the version of a serialized class by specializing the 'version' template class: ============================== template <typename T> struct version { BOOST_STATIC_CONSTANT(unsigned int, value = 0); }; ... template <> struct version<MyType> { BOOST_STATIC_CONSTANT(unsigned int, value = 1); }; ============================== However, this approach does not work if 'MyType' is of the form (see [1]): ============================== template <typename T> struct Foo { struct MyType { int data1; }; }; template <typename T> struct version<Foo<T>::MyType> // ERROR { BOOST_STATIC_CONSTANT(unsigned int, value = 1); }; ============================== It's not possible for the compiler to deduce the enclosing type, so this doesn't work. However, if MyType can be identified by a metafunction, then I can use enable_if to select the specialization of 'version' that I want. However, this requires support from 'version' itself: ============================== template <typename T, typename Enable = void> // NOTE new template parameter struct version { BOOST_STATIC_CONSTANT(unsigned int, value = 0); }; ... template <typaneme T> struct version<MyType, typename boost::enable_if<is_mytype<T> >::type> { BOOST_STATIC_CONSTANT(unsigned int, value = 1); }; ============================== So, my proposal is simply to add this extra template parameter to 'version'. I do not believe other uses of 'version' will be affected, but it would not surprise me if I've overlooked something. Presumably the same modification could be made to implementation_level etc. A patch (for 'version' only) against trunk is enclosed below. Comments are welcome! Thanks, -Gabe [1] http://boost.2283326.n4.nabble.com/serialization-versioning-for-class-neste… =================================================================== --- version.hpp (revision 81723) +++ version.hpp (working copy) @@ -32,7 +32,7 @@ // default version number is 0. Override with higher version // when class definition changes. -template<class T> +template<class T, class Enable=void> struct version { template<class U> @@ -53,8 +53,8 @@ }; #ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION -template<class T> -const int version<T>::value; +template<class T, class Enable> +const int version<T, Enable>::value; #endif } // namespace serialization ===================================================================

5 12

Inspect Report
by Daniel James 07 Dec '12

07 Dec '12

Hi, The snapshot builds and inspect results haven't been running for some time, so I've added running the inspect script to the documentation build for more up to date results. You can see them at: http://boost.cowic.de/rc/docs-inspect-trunk.html http://boost.cowic.de/rc/docs-inspect-release.html These are generated after building documentation, which is not exactly the same as the final release, but it's close. Daniel

4 10

[context] asm_context_sources breaking regression testing for WinCE
by David Deakins 07 Dec '12

07 Dec '12

Hi Oliver, I finally got a little bit of time to investigate recent strange behavior on the VeecoFTC regression tester and found that the build jamfile for the context library is halting Boost.Build during the regression tests. It appears that, when it can't find an appropriate architecture to use, it actually generates an argument error in try-one-generator-really. I attached the output of the bjam.log and perhaps it will be useful for investigating. Let me know if you would like me to try anything. Thanks, -Dave

2 12

[iterator] UB when implicitly using default constructed counting_iterator<unsigned>
by Peter Sommerlad 07 Dec '12

07 Dec '12

Hi Jeffrey, hi all, I believe the usability of counting iterator could be improved, by value-initializing its Iterator type in the default constructor, because integral types won't be initialized by its default constructor. This can lead to hard to recognize user errors, e.g., when wrapping such a counting iterator with a filter iterator. counting_iterator is special in that sense, because to my understanding it is intended to adapt integral types to become iterators. And a default initialized scalar type, isn't. I suggest a one line change: counting_iterator() { } should become counting_iterator() : super_t(Incrementable()) { } The following example program shows the interesting UB, because the 3rd argument of make_filter_iterator, default constructs a counting_iterator<unsigned>(). Any thoughts? Objections? Teachings... Regards Peter. =====>8 #include <iostream> #include <boost/iterator/filter_iterator.hpp> #include <boost/iterator/counting_iterator.hpp> #include <algorithm> #include <iterator> #include <functional> struct is_prime{ bool operator()(unsigned int val) const { if (val < 2) return false; using std::placeholders::_1; auto ce=boost::make_counting_iterator(val); return ce==std::find_if_not(boost::make_counting_iterator(2u),ce, bind(std::modulus<unsigned>{},val,_1)); } }; int main(){ std::copy_n(boost::make_filter_iterator(is_prime{},boost::make_counting_iterator(1u) // if the following line is omitted we have undefined behavior, because of uninitialized unsigned value // ,boost::make_counting_iterator(std::numeric_limits<unsigned>::max()) // must be different from above value ),40,std::ostream_iterator<unsigned>{std::cout,", "}); } =====8< -- Prof. Peter Sommerlad Institut für Software: Bessere Software - Einfach, Schneller! HSR Hochschule für Technik Rapperswil Oberseestr 10, Postfach 1475, CH-8640 Rapperswil http://ifs.hsr.ch http://cute-test.com http://linticator.com http://includator.com tel:+41 55 222 49 84 == mobile:+41 79 432 23 32 fax:+41 55 222 46 29 == mailto:peter.sommerlad@hsr.ch

3 2

[coroutine] permission to merge to boost-release?
by Oliver Kowalke 07 Dec '12

07 Dec '12

Hello, because the merge window for new libraries is closed on Monday I'd like to ask for permission to merge boost.coroutine into boost-release. regards, Oliver

2 2

Re: [boost] [iterator] UB when implicitly using default constructed counting_iterator<unsigned>
by Peter Sommerlad 07 Dec '12

07 Dec '12

Hi Jeff On 01.12.2012, at 02:53, Jeffrey Lee Hellrung, Jr. wrote: >> And a default >> initialized scalar type, isn't. >> > > "isn't"...what, exactly? it isn't initialized with a defined value. struct X{ X(){} unsigned x; }; void foo(){ X y; // -> y.x has an uninitialized value AFAIK if it is local } that is the situation we run into with the default constructed counting_iterator<unsigned>() > I'm not opposed to giving defined behavior to a default constructed > counting_iterator< [integral type] >, I'm just not sure what that defined > behavior should be. Maybe I'm over-analyzing it... I still believe the most simple change I suggested is enough (at least it would cover my situation well enough). Those input iterators where a default constructed one is the end iterator is IMHO more of an exception, because it is a special case for the stream iterators. Your idea with std::numberic_limits< Iterator >::max() requires a much more complex solution with template meta programming, i.e., enable_if<is_arithmetic<Iterator>> or similar. And it won't provide the default value of Iterator, which is zero in the case of the built-in arithmetic types, i.e., unsigned(). What do you think? Regards Peter. -- Prof. Peter Sommerlad Institut für Software: Bessere Software - Einfach, Schneller! HSR Hochschule für Technik Rapperswil Oberseestr 10, Postfach 1475, CH-8640 Rapperswil http://ifs.hsr.ch http://cute-test.com http://linticator.com http://includator.com tel:+41 55 222 49 84 == mobile:+41 79 432 23 32 fax:+41 55 222 46 29 == mailto:peter.sommerlad@hsr.ch

7 21

[array] last check in break serialization for array
by Robert Ramey 06 Dec '12

06 Dec '12

A particular test in the serialization library spontaneously has broken. By "spontaneously" I mean that I haven't checked anything in lately. The test is test_array_xml_warchive in the serialization library test matrix. Here are a few facts: a) I haven't checked anything in so the serialization library itself hasn't changed. b) It occurs on all GCC platforms. c) it "seems" to have started around 30 November d) it occurs only on the trunk - all these tests have been run since 30 November e) it doesn't occur on the release branch - none of these tests run since 30 November f) it occours on my development machine. Note that I use release branch for all testing - except for the serialization library itself which I use the trunk version. g) The nature of the error suggests that it is related to memory allocation/deallocation > From all of the above I'm looking at change on the release branch #81635 > (or there abouts) by glenfe Merged revision(s) 81608-81610 from trunk: Optimization: Add specializations of make_array_helper, allocate_array_helper, and array_deleter for fixed size arrays to avoid storing size. ........ Consistent formatting across overloads of make_shared and allocate_shared (array forms). ........ More consistency in type parameters in helper details of allocate_shared and make_shared. ... Does anyone have any insight into this? Robert Ramey

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[Interprocess] message_queue should use timed_lock
by Hartmut Kaiser 06 Dec '12

06 Dec '12

Hey, I'm running into a timing issue with interprocess::message_queue even when I use the timed send and received functions: One end: if (!mq_->timed_receive(&msg, sizeof(msg), recvd_size, priority, boost::get_system_time() + boost::posix_time::milliseconds(1))) { // ... return false; } // ... The other end: while (!mq_->timed_send(&msg, sizeof(msg), 0, boost::get_system_time() + boost::posix_time::milliseconds(1))) { break; } (mq_ is a shared_ptr<message_queue>) here both ends sit forever inside the timed_receive/timed_send function, both waiting to acquire a lock (ipc/message_queue.hpp, lines 702 and 799), which is held by a third participating process. Shouldn't this lock be using a timed_lock to allow to maintain the API post condition (i.e. returning after the given amount of time in any case)? Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

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[trunk-tests] msvc-8.0 internal compiler error
by Oliver Kowalke 06 Dec '12

06 Dec '12

Hi, msvc-8.0 generates an internal compiler error in the regression tests for boost.coroutine (tests in boost-trunk - http://www.boost.org/development/tests/trunk/developer/output/VC8%20jc-bell… ). Is it possible to prevent this error a code modification? Other versions like msvc-9.0/10.0/11.0/12.0 do pass the regression test. Oliver test_coroutine.cpp ..\boost/mpl/eval_if.hpp(41) : fatal error C1001: An internal error has occurred in the compiler. (compiler file 'msc1.cpp', line 1393) To work around this problem, try simplifying or changing the program near the locations listed above. Please choose the Technical Support command on the Visual C++ Help menu, or open the Technical Support help file for more information ..\boost/foreach.hpp(364) : see reference to class template instantiation 'boost::mpl::eval_if<C,F1,F2>' being compiled with [ C=boost::mpl::false_, F1=boost::range_const_iterator<boost::coroutines::coroutine<int (void)>>, F2=boost::range_mutable_iterator<boost::coroutines::coroutine<int (void)>> ] ..\libs\coroutine\test\test_coroutine.cpp(415) : see reference to class template instantiation 'boost::foreach_detail_::foreach_iterator<T,C>' being compiled with [ T=coro_int_void, C=boost::mpl::false_ ] Internal Compiler Error in C:\Program Files (x86)\MSVC8\VC\BIN\cl.exe. You will be prompted to send an error report to Microsoft later.

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[compond_file_binary] Gauging interest in a possible library submission.
by А В 06 Dec '12

06 Dec '12

Hi, all. Is there any interest in a cross-platform C++ library which allows to create/read/write binary compound files? Briefly, compound file is filesystem for storing files and directories within a single file on a disk. Initially compound file format is developed by Microsoft and now is the part of Microsoft's Open Specifications Documentation. Compound files are used across various platforms and applications, and not restricted by some specific domain. In general, any application can store information in such a way. I've found on the Internet interest in such library and decided to implement it. Additional information can be found here: Article on the Wikipedia: http://en.wikipedia.org/wiki/Compound_File_Binary_Format Benefits of Compound Files: http://msdn.microsoft.com/en-us/library/windows/desktop/aa378938(v=vs.85).a… [MS-CFB] Open specification for compound files: http://msdn.microsoft.com/en-us/library/dd942138.aspx Regards, Alexander Voitenko.

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generating docu fails
by Oliver Kowalke 05 Dec '12

05 Dec '12

Hello, 'quickbook context.qbk' generates context.xml but generating the html via bjam fails: /boost_1_52_0/tools/build/v2/build/generators.jam:1085: in ensure-type from module generators error: target { context.qbk. } has no type /boost_1_52_0/tools/build/v2/build/generators.jam:1319: in generators.construct from module generators /boost_1_52_0/tools/build/v2/build/targets.jam:1495: in construct from module object(typed-target)@927 /boost_1_52_0/tools/build/v2/build/targets.jam:1298: in object(typed-target)(a)927.generate from module object(typed-target)@927 /boost_1_52_0/tools/build/v2/build/targets.jam:732: in generate-really from module object(main-target)@958 /boost_1_52_0/tools/build/v2/build/targets.jam:704: in object(main-target)(a)958.generate from module object(main-target)@958 /boost_1_52_0/tools/build/v2/build/targets.jam:258: in object(project-target)(a)926.generate from module object(project-target)@926 /boost_1_52_0/tools/build/v2/build-system.jam:736: in load from module build-system /boost_1_52_0/tools/build/v2/kernel/modules.jam:283: in import from module modules /boost_1_52_0/tools/build/v2/kernel/bootstrap.jam:142: in boost-build from module /boost_1_52_0/boost-build.jam:17: in module scope from module how can it be fixed? Oliver

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[mpl] [bimap] BOOST_MPL_LIMIT_METAFUNCTION_ARITY issue on g++ 4.6.3 and boost 1.50
by Adam Lach 05 Dec '12

05 Dec '12

Hi, I have already asked for help on Boost.users, but with no luck, see here <http://boost.2283326.n4.nabble.com/Problems-in-boost-mpl-aux-template-arity…> . Since then I have managed to reproduce this problem in a simpler case: #define BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS #define BOOST_MPL_LIMIT_METAFUNCTION_ARITY 10 #include <boost/mpl/inherit.hpp> #include <boost/bimap.hpp> struct S0 {}; struct S1 {}; struct S2 {}; struct S3 {}; struct S4 {}; struct S5 {}; template<typename T0, typename T1, typename T2, typename T3, typename T4, typename T5> struct example : boost::mpl::inherit<T0,T1,T2,T3,T4,T5> {}; int main() { example<S0,S1,S2,S3,S4,S5> pasta; return 0; } The weird thing is that it occurs only if bimap.hpp is included. Please help. Thank you in advance, Adam Lach -- View this message in context: http://boost.2283326.n4.nabble.com/boost-mpl-bimap-BOOST-MPL-LIMIT-METAFUNC… Sent from the Boost - Dev mailing list archive at Nabble.com.

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Looking for someone with MSVC 8 or MSVC 9
by Marshall Clow 04 Dec '12

04 Dec '12

One of the string_ref tests is failing on these two compilers - neither of which I have access to. I would appreciate some help debugging this failure [ FWIW, the same tests pass on MSVC 10 and 11 ] Thanks in advance! -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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Re: [boost] [iterator] UB when implicitly using default constructed counting_iterator<unsigned>
by Peter Sommerlad 04 Dec '12

04 Dec '12

Hi Jeff, On 04.12.2012, at 18:59, Jeffrey Lee Hellrung, Jr. wrote: > On Sun, Dec 2, 2012 at 8:41 AM, Peter Sommerlad <peter.sommerlad(a)hsr.ch>wrote: > just consider the following small program: >> >> #include <iostream> >> #include <boost/iterator/counting_iterator.hpp> >> >> int main(){ >> std::cout << unsigned() << '\n'; // zero >> std::cout << *boost::counting_iterator<unsigned>()<< '\n';// >> undefined behavior >> } >> > > Not quite UB :) It just outputs an undefined value. It won't blow up the > moon, for example. That is not true. According to the standard reading an uninitialized value incurs undefined behavior. While in practice your computer might not explode, it is inherently unsafe and unportable to rely on something like this. See below. Therefore my concerns (I am a regular attendant of the standard committee meetings, so I can check with the real experts about that, if you doubt). 4.1 Lvalue-to-rvalue conversion [conv.lval] • 1 A glvalue (3.10) of a non-function, non-array type T can be converted to a prvalue.53 If T is an incomplete type, a program that necessitates this conversion is ill-formed. If the object to which the glvalue refers is not an object of type T and is not an object of a type derived from T, or if the object is uninitialized, a program that necessitates this conversion has undefined behavior. If T is a non-class type, the type of the prvalue is the cv-unqualified version of T. Otherwise, the type of the prvalue is T.54 > > I understand your concerns, I think, but I believe it's somewhat misguided. > I believe your proposal could do at least as much to mask errors as it will > to find errors. Indeed, your original example would've silently worked as > expected (with the present implementation of filter_iterator, anyway) with > your proposed change, even though it's (still) incorrect usage. I still believe it is much better for a library to not incur silently undefined behavior, but to provide a defined default value, even if it is unusable in general, but detectable. if I would have used 0 as the start iterator in the original example instead of 1 I would have seen something is wrong with my unit tests. However, the undefined behavior didn't help me detecting it. Regards Peter. -- Prof. Peter Sommerlad Institut für Software: Bessere Software - Einfach, Schneller! HSR Hochschule für Technik Rapperswil Oberseestr 10, Postfach 1475, CH-8640 Rapperswil http://ifs.hsr.ch http://cute-test.com http://linticator.com http://includator.com tel:+41 55 222 49 84 == mobile:+41 79 432 23 32 fax:+41 55 222 46 29 == mailto:peter.sommerlad@hsr.ch

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[BGL] status of maximum adjacency search
by Fernando Vilas 03 Dec '12

03 Dec '12

Hi, What remains to get ticket 6780 ready to commit? -- Thanks, Fernando Vilas fvilas(a)iname.com

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[functional/hash] error: more than one instance of overloaded function "fpclassify" matches the argument list:
by Vicente J. Botet Escriba 02 Dec '12

02 Dec '12

Hi, there is a compile error that making fail all the tests in this tester. Could someone take care of it? Best, Vicente Test output: lazy piranha fedora 17 64 C++11 - thread - async__async_p / intel-linux-13.0.1 Rev 81655 / Sat, 1 Dec 2012 18:49:57 +0000 *Report Time: *Sun, 2 Dec 2012 12:54:01 +0000 Compile [2012-12-02 03:35:40 UTC]: fail "/opt/intel/bin/icpc" -c -xc++ -std=c++11 -O0 -g -w2 -inline-level=0 -pthread -fPIC -wd1418 -wd193,304,383,444 -wd2415 -wd593,981 -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -DBOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED -DBOOST_THREAD_USE_DLL=1 -I".." -c -o "/home/michael/boost_testing/results/boost/bin.v2/libs/thread/test/async__async_p.test/intel-linux-13.0.1/debug/threading-multi/sync/futures/async/async_pass.o" "../libs/thread/test/sync/futures/async/async_pass.cpp" ../boost/functional/hash/detail/hash_float.hpp(214): error: more than one instance of overloaded function "fpclassify" matches the argument list: function "fpclassify(double)" function "std::fpclassify(double)" argument types are: (double) switch (fpclassify(v)) { ^ detected during: instantiation of "std::size_t={unsigned long} boost::hash_detail::float_hash_value(T) [with T=double]" at line 312 of "../boost/functional/hash/hash.hpp" instantiation of "boost::hash_detail::float_numbers<T>::type boost::hash_value(T) [with T=double]" at line 413 of "../boost/functional/hash/hash.hpp" compilation aborted for ../libs/thread/test/sync/futures/async/async_pass.cpp (code 2) TinyUrl <javascript:make_tinyurl()>

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Fwd: [iterator] UB when implicitly using default constructed counting_iterator<unsigned>
by Jeffrey Lee Hellrung, Jr. 01 Dec '12

01 Dec '12

[Sorry, forgot to reply-all.] ---------- Forwarded message ---------- From: Jeffrey Lee Hellrung, Jr. <jeffrey.hellrung(a)gmail.com> Date: Fri, Nov 30, 2012 at 5:53 PM Subject: Re: [boost][iterator] UB when implicitly using default constructed counting_iterator<unsigned> To: Peter Sommerlad <peter.sommerlad(a)hsr.ch> On Fri, Nov 30, 2012 at 1:14 AM, Peter Sommerlad <peter.sommerlad(a)hsr.ch>wrote: > Hi Jeffrey, hi all, > > I believe the usability of counting iterator could be improved, by > value-initializing its Iterator type in the default constructor, because > integral types won't be initialized by its default constructor. This can > lead to hard to recognize user errors, e.g., when wrapping such a counting > iterator with a filter iterator. > > counting_iterator is special in that sense, because to my understanding it > is intended to adapt integral types to become iterators. And a default > initialized scalar type, isn't. > "isn't"...what, exactly? > I suggest a one line change: > > counting_iterator() { } > > should become > > counting_iterator() : super_t(Incrementable()) { } > Well, that's one thing you can do... > The following example program shows the interesting UB, because the 3rd > argument of make_filter_iterator, default constructs a > counting_iterator<unsigned>(). > > Any thoughts? Objections? Teachings... > > Regards > Peter. > > =====>8 > #include <iostream> > #include <boost/iterator/filter_iterator.hpp> > #include <boost/iterator/counting_iterator.hpp> > #include <algorithm> > #include <iterator> > #include <functional> > > struct is_prime{ > bool operator()(unsigned int val) const { > if (val < 2) return false; > using std::placeholders::_1; > auto ce=boost::make_counting_iterator(val); > return ce==std::find_if_not(boost::make_counting_iterator(2u),ce, > > bind(std::modulus<unsigned>{},val,_1)); > } > }; > int main(){ > > std::copy_n(boost::make_filter_iterator(is_prime{},boost::make_counting_iterator(1u) > // if the following line is omitted we have undefined behavior, > because of uninitialized unsigned value > // > ,boost::make_counting_iterator(std::numeric_limits<unsigned>::max()) // > must be different from above value > ),40,std::ostream_iterator<unsigned>{std::cout,", > "}); > } > > =====8< The thing that bothers me about this is that a default-constructed iterator frequently is an end iterator; indeed, that's the assumption that filter_iterator appears to be making if no end iterator is supplied. So if the default-constructed iterator is not an end iterator, and you're wrapping it with a filter_iterator and not explicitly supplying the end, I'd say you're automatically asking for trouble, regardless of whether you're using a counting_iterator or not. On the other hand, I'm not sure what a sensible default value is for counting_iterator< [integral type] >; 0 is almost never going to be the end value; std::numeric_limits<>::max() might be a better choice, but really the end value is context-dependent. I'm not opposed to giving defined behavior to a default constructed counting_iterator< [integral type] >, I'm just not sure what that defined behavior should be. Maybe I'm over-analyzing it... - Jeff

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