July 2013 - Boost - lists.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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Is there any interest in a library for actor programming?
by Charousset, Dominik 28 May '14

28 May '14

Hi, is there any interest in a library for actor programming? The library we've developed is a C++11 open source library named "libcppa". It is currently released under LGPL2, but re-releasing the library under the boost license is not an issue. You'll find all important links and ressources either under http://libcppa.org or on the GitHub project page: https://github.com/Neverlord/libcppa, including a user manual as HTML or PDF. We've also submitted a paper to the C++Now conference. What is actor programming? For those of you who aren't yet familiar with the actor model: actors basically represent tasks or services that communicate via message passing. In libcppa, actors are very lightweight (you can spawn literally millions of them) and scheduled cooperatively using a thread pool (although actors are allowed to opt-out of the cooperative scheduling). Some of the main strengths of this programming paradigm are: (1) network transparency, (2) race conditions are avoided by design, (3) a strong failure model that enables developers to build reliable distributed systems, and (4) the actor model addresses both concurrency (multiple actors on one host) and distribution (any number of actors on any number of hosts). Here's the classical hello world example: ---------------------------------------------------------------------------------- #include <string> #include <iostream> #include "cppa/cppa.hpp" using namespace std; using namespace cppa; void mirror() { // wait for messages become ( // invoke this lambda expression if we receive a string on_arg_match >> [](const string& what) { // prints "Hello World!" via aout (thread-safe cout wrapper) aout << what << endl; // replies "!dlroW olleH" reply(string(what.rbegin(), what.rend())); // terminates this actor ('become' otherwise loops forever) self->quit(); } ); } void hello_world(const actor_ptr& buddy) { // send "Hello World!" to our buddy ... sync_send(buddy, "Hello World!").then( // ... and wait for a response on_arg_match >> [](const string& what) { // prints "!dlroW olleH" aout << what << endl; } ); } int main() { // create a new actor that calls 'mirror()' auto mirror_actor = spawn(mirror); // create another actor that calls 'hello_world(mirror_actor)' spawn(hello_world, mirror_actor); // wait until all other actors we have spawned are done await_all_others_done(); // run cleanup code before exiting main shutdown(); } ---------------------------------------------------------------------------------- A message is simply a tuple of values that is pattern matched at the receiver. For example, " on_arg_match >> [](const string& what) {...}" defines a message handler that is called whenever a tuple with one single string element arrives. "on_arg_match" simply defines a pattern that matches the signature of the given lambda. Please have a look at the examples folder on GitHub (https://github.com/Neverlord/libcppa/tree/master/examples) or at the user manual (http://neverlord.github.io/libcppa/manual/) if you want to see more examples. Best regards, Dominik Charousset

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required toolsets
by Steven Watanabe 15 May '14

15 May '14

AMDG The list of required toolsets in explicit-failures-markup.xml is out-dated. Therefore, if no one objects, I propose setting it to the following: msvc-10.0, msvc-11.0, gcc-4.6, gcc-4.7, clang-darwin-11, clang-darwin-4.2.1, clang-linux-3.1, clang-linux-3.2, gcc-mingw-4.7, gcc-mingw-4.6 (two releases of each major compiler that appears in both the trunk and release regression tests) The sole effect of this is to determine which toolsets appear in the issues list: http://www.boost.org/development/tests/trunk/developer/issues.html In Christ, Steven Watanabe

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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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boost::optional -- updates for C++11 move semantics
by Diggory Hardy 10 Apr '14

10 Apr '14

Dear list, I wanted something like boost::optional, but with support for move- construction/assignment, so I went ahead and had a go at patching it. Attached is based on boost 1.49 (Ubuntu package). Could someone please review? I've not contributed to boost before. The changes at least aren't too complicated, but: 1) I'm not entirely sure if the move constructor (line 636) and swap function (line 1046) are implemented in the best way (also see line 279), 2) and I have no idea how is_[not_]reference_tag (line 486) works. 3) There should maybe also be a unit test. Of course, I am happy for my contributions to be published under the boost licence. Regards, Diggory

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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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C++03 and C++11 ABI compatibility for compiled libraries
by Andrey Semashev 24 Jan '14

24 Jan '14

Hi, I would like to raise the issue of binary compatibility of compiled Boost libraries between C++03 and C++11. I faced this problem with gcc on Linux, but other compilers and platforms may be affected as well. To summarize the problem: * Most, if not all Linux distributions build packages in C++03 mode. This is also the default in gcc. * Some Boost libraries conditionally use C++11 features in their binary interfaces (see [1] as an example). This makes C++03 and C++11 versions of the library binary incompatible. * Given that, users are unable to use C++11 in their code that uses Boost because of linker failures. I don't have the complete list of the offending C++11 features that break ABI, but it would seem that at least scoped enums and rvalue references are among them. Are there any more? I would like to hear opinions on the possible course of action to tackle this problem. Currently, I see 2 choices: 1. Avoid using C++11 features in binary interfaces. This may also mean avoiding STL types in binary interfaces, if they differ between C++03 and C++11 (I didn't verify that). This is my suggested hotfix solution for Boost.Filesystem [1] and the approach I took in Boost.Log. Obviously, this cripples code and error prone, but it keeps a single binary that can be used from any flavor of C++ on the user's side. 2. Compile different versions of Boost libraries, for each supported C++ version. The C++ version should be encoded into the library file names, so that different versions can coexist. This would require changes in Boost.Build and autolinking support code, but I think this would be a better long-term solution. Opinions? [1] https://svn.boost.org/trac/boost/ticket/6779

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[Macro]Test Case grouping using Traits
by Hemanth Choudary M V (RBEI/ETA1) 13 Jan '14

13 Jan '14

Hello, I have observed that in native unit test framework(c++), there is an option to group test cases using attributes which are reflected as traits in the Test Explorer window in MS VS2012. Following is a an example of the same: BEGIN_TEST_METHOD_ATTRIBUTE(TestMethod3) TEST_OWNER(L"SuperMan") TEST_PRIORITY(2) TEST_METHOD_ATTRIBUTE(L"Category",L"Slow") END_TEST_METHOD_ATTRIBUTE() TEST_METHOD(TestMethod3) { Assert::AreEqual(2,6); } How can this be achieved via Boost Unit Test Library? Are there macros to achieve the same? Mit freundlichen Grüßen / Best Regards, Hemanth Choudary MV RBEI/ETA1

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[filesystem] fix recur_dir_itr_imp::increment(system::error_code* ec) in 1.54.0
by claudio.bley＠gmail.com 19 Dec '13

19 Dec '13

Hi. What's happening to the filesystem library? It seems there's no progress on any tickets in the bug tracker? Referring to https://svn.boost.org/trac/boost/ticket/6821#comment:5 Could we get this fix into 1.54.0, please? BTW, sorry for any confusion - I "managed" to comment on the wrong ticket... https://svn.boost.org/trac/boost/ticket/5403 would've been more appropriate, I guess. Claudio -- Claudio

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RFC: edit_distance / edit_alignment library
by Erik Erlandson 18 Dec '13

18 Dec '13

Boost Community, I cooked up a library that provides a pair of functions: edit_distance() and edit_alignment(). The library currently lives here: https://github.com/erikerlandson/edit_distance Some short example programs are here: https://github.com/erikerlandson/edit_distance/tree/master/examples A few example expressions: // the edit distance (aka levenshtein distance) unsigned dist = edit_distance("abc", "bcd"); // using a custom cost function for insertion, deletion, substitution unsigned dist = edit_distance("abc", "bcd", custom_cost_function()); // accepts arbitrary sequences, ranges, range adaptors unsigned dist = edit_distance(as_vector("abc"), as_list("bcd") | boost::adaptors::reversed); // obtain the edit distance and the list of the edit operation codes (in output iterator) unsigned dist = edit_alignment("abc", "bcd", std::ostream_iterator<edit_opcode>(std::cout, "")).second; // adaptors to add edit operation costs and sequence elements to the edit operation output unsigned dist = acquire<elements>(acquire<costs>(edit_alignment))("abc", "bcd", std::ostream_iterator<boost::tuple<edit_opcode, unsigned, char, char> >(std::cout, "")).second; I'm interested in community feedback on whether these would be a useful addition to boost::algorithms. I envision these as the first additions to an eventually-larger library of other kinds of string distances, dynamic programming, and other algorithms for sequence alignment.

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[tweener] Doxygen documentation issues
by Julien Jorge 05 Nov '13

05 Nov '13

Hi, I am writing the documentation of Boost.Tweener and I encounter various difficulties. One of them is the generation of the class documentation with doxygen. It seems that it cannot extract the class and member documentation from .ipp files. I like to document the methods of my classes near the implementation. In Boost.Tweener, most of the class documentation is then in the .ipp files and I have written the following lines in the Jamfile.v2: import quickbook ; using boostbook ; using doxygen ; doxygen reference : [ glob ../../../boost/tweener/*.hpp ] [ glob ../../../boost/tweener/detail/*.hpp ] [ glob ../../../boost/tweener/detail/impl/*.ipp ] [ glob ../../../boost/tweener/detail/impl/easing/*.ipp ] [ glob ../../../boost/tweener/easing/*.hpp ] But when I try to build the documentation, I have the following error: boost_1_52_0/tools/build/v2/build/generators.jam:1085: in ensure-type from module generators error: target { ../../../boost/tweener/detail/impl/tweener_group.ipp. } has no type Moreover, if I remove the ipp files, the generation of the documentation does not fail but the doxygen documentation is not extracted, except for the private members. So, how can I also disable the extraction of the private members in the documentation? You can check the Jamfile.v2 in the git repository of the project: http://libclaw.git.sourceforge.net/git/gitweb.cgi?p=libclaw/boost-tweener;a… Regards, Julien

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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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How to center an element in Boost QuickBook?
by Niall Douglas 10 Oct '13

10 Oct '13

As the documentation for proposed Boost.AFIO comes together for this week's GSoC Milestone 1 (feel free to check it out at https://ci.nedprod.com/job/Boost.AFIO%20Build%20Documentation/Boost.AFIO_Doc umentation/?), a problem has emerged. We'd like a matrix table containing ticks and crosses, and building such a thing in QuickBook is easy. However, we'd also like to center the ticks and crosses in each table cell, otherwise it looks poor. Is there some way I haven't realized of aligning content in Boost QuickBook, or even BoostBook itself? The DocBook documentation suggests one can do a '''<entry align="center">'''__tick__'''</entry>''' (the triple single ticks escape from QuickBook into BoostBook). However unfortunately BoostBook defines CSS which overrides the per-cell alignment :( Thanks in advance for the help. Niall --- Opinions expressed here are my own and do not necessarily represent those of BlackBerry Inc.

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lots of warning with gcc-4.8.1 + boost-1.54.0
by Neal Becker 04 Oct '13

04 Oct '13

Lots of warnings like this: ./boost/bind/arg.hpp:37:22: warning: typedef ‘T_must_be_placeholder’ locally defined but not used [-Wunused-local-typedefs] when building 1.54.0 with gcc-4.8.1 (fedora f19)

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[accumulators] Help understanding implementation of weighted accumulators
by Gabriel Redner 02 Oct '13

02 Oct '13

Hi folks, I am trying to implement a weighted accumulator, but I'm having trouble understanding a few things about the existing ones. Looking at the implementation of weighted_sum, I see (weighted_sum.hpp:37): template<typename Args> weighted_sum_impl(Args const &args) : weighted_sum_( args[parameter::keyword<Tag>::get() | Sample()] * numeric::one<Weight>::value ) { } My questions are: - It's taking the first sample from the args and multiplying it by a weight of 1. Isn't this wrong - ignoring the real weight of this sample? Shouldn't this produce incorrect results? - I've never understood anyways how there can be an initial argument during construction of the accumulator. I haven't found any explanation in the docs beyond "Maybe there is an initial value in the argument pack". Maybe? How? Probably more questions later. Thanks, -Gabe

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[thread] semaphore
by Tim Blechmann 02 Oct '13

02 Oct '13

hi all, i've submitted an implementation of semaphores for boost.thread to trac [1]. they provide an interface similar to boost.interprocess semaphores, with the exception of having chrono-style try_wait_for and try_wait_until members for timed_wait. the patch provides the following implementations: * win32 semaphores (tested with windows 8) * posix semaphores (tested with linux) * dispatch semaphores (tested with osx 10.8) * mutex/condition_variable/counter emulation the native implementations are much faster than the fallback, in microbenchmarks with high contention, i've seen a speedup of 30 to 80. would be great if they can be incorporated into boost.thread. comments/suggestions on the API are highly appreciated. cheers, tim [1] https://svn.boost.org/trac/boost/ticket/8797

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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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[thread] synchronized_value: value and move semantics
by Vicente J. Botet Escriba 24 Sep '13

24 Sep '13

Hi, boost::synchronized_value (not released yet [1][2][3]) is based on [4]. See below part of this paper adapted to the Boost.Thread interface. Currently boost::synchronized_value is in addition Copyable and Swappable. I was wondering if it is worth adding value and move semantics to synchronized_value. Making it EqualityComparable, LessThanComparable and Movable if the underlying type satisfy these requirements will allow to store them on a Boost.Container/C++11 container. Do you see something completely wrong with this addition? Has some of you had a need for this? Could you share the context? Best, Vicente [1] https://svn.boost.org/svn/boost/trunk/boost/thread/synchronized_value.hpp [2] https://svn.boost.org/svn/boost/trunk/libs/thread/example/synchronized_valu… [3] https://svn.boost.org/svn/boost/trunk/libs/thread/example/synchronized_pers… [4] "Enforcing Correct Mutex Usage with Synchronized Values" by Anthony Williams http://www.drdobbs.com/cpp/enforcing-correct-mutex-usage-with-synch/2252002… ------------- [section The Problem with Mutexes] The key problem with protecting shared data with a mutex is that there is no easy way to associate the mutex with the data. It is thus relatively easy to accidentally write code that fails to lock the right mutex - or even locks the wrong mutex - and the compiler will not help you. std::mutex m1; int value1; std::mutex m2; int value2; int readValue1() { boost::lock_guard<boost::mutex> lk(m1); return value1; } int readValue2() { boost::lock_guard<boost::mutex> lk(m1); // oops: wrong mutex return value2; } Moreover, managing the mutex lock also clutters the source code, making it harder to see what is really going on. The use of synchronized_value solves both these problems - the mutex is intimately tied to the value, so you cannot access it without a lock, and yet access semantics are still straightforward. For simple accesses, synchronized_value behaves like a pointer-to-T; for example: boost::synchronized_value<std::string> value3; std::string readValue3() { return *value3; } void setValue3(std::string const& newVal) { *value3=newVal; } void appendToValue3(std::string const& extra) { value3->append(extra); } Both forms of pointer dereference return a proxy object rather than a real reference, to ensure that the lock on the mutex is held across the assignment or method call, but this is transparent to the user. [endsect] [/The Problem with Mutexes] [section Beyond Simple Accesses] The pointer-like semantics work very well for simple accesses such as assignment and calls to member functions. However, sometimes you need to perform an operation that requires multiple accesses under protection of the same lock, and that's what the synchronize() method provides. By calling synchronize() you obtain an strict_lock_ptr object that holds a lock on the mutex protecting the data, and which can be used to access the protected data. The lock is held until the strict_lock_ptr object is destroyed, so you can safely perform multi-part operations. The strict_lock_ptr object also acts as a pointer-to-T, just like synchronized_value does, but this time the lock is already held. For example, the following function adds a trailing slash to a path held in a synchronized_value. The use of the strict_lock_ptr object ensures that the string hasn't changed in between the query and the update. void addTrailingSlashIfMissing(boost::synchronized_value<std::string> & path) { boost::strict_lock_ptr<std::string> u=path.synchronize(); if(u->empty() || (*u->rbegin()!='/')) { *u+='/'; } } [endsect] [/Beyond Simple Accesses] [section Operations Across Multiple Objects] Though synchronized_value works very well for protecting a single object of type T, nothing that we've seen so far solves the problem of operations that require atomic access to multiple objects unless those objects can be combined within a single structure protected by a single mutex. One way to protect access to two synchronized_value objects is to construct a strict_lock_ptr for each object and use those to access the respective protected values; for instance: synchronized_value<std::queue<MessageType> > q1,q2; void transferMessage() { strict_lock_ptr<std::queue<MessageType> > u1 = q1.synchronize(); strict_lock_ptr<std::queue<MessageType> > u2 = q2.synchronize(); if(!u1->empty()) { u2->push_back(u1->front()); u1->pop_front(); } } This works well in some scenarios, but not all - if the same two objects are updated together in different sections of code then you need to take care to ensure that the strict_lock_ptr objects are constructed in the same sequence in all cases, otherwise you have the potential for deadlock. This is just the same as when acquiring any two mutexes. In order to be able to use the dead-lock free lock algorithms we need to use instead unique_lock_ptr, which is Lockable. synchronized_value<std::queue<MessageType> > q1,q2; void transferMessage() { unique_lock_ptr<std::queue<MessageType> > u1 = q1.unique_synchronize(boost::defer_lock); unique_lock_ptr<std::queue<MessageType> > u2 = q2.unique_synchronize(boost::defer_lock); boost::lock(u1,u2); // dead-lock free algorithm if(!u1->empty()) { u2->push_back(u1->front()); u1->pop_front(); } } [endsect] [/Operations Across Multiple Objects]

6 19

[Operators] empty_base should be untemplated?
by Andrew Ho 21 Sep '13

21 Sep '13

I've noticed about the empty_base class is that it's templated with type T, and I don't think it should be. Fyi, the empty_base class is there to turn multiple inheritance into a single inheritance chain (due to compiler deficiencies/object size bloat on at least Visual Studio). I don't see why this empty_base should be templated, and it would be better suited if it wasn't since all I can think it does is make the compiler work harder. Does anyone know why it was templated to begin with? Additionally, are we safe to change empty_base to be not use templates?

4 4

[asio] boost::asio::async_connect reports success on failure
by Ben Pope 13 Sep '13

13 Sep '13

Hi all, I've found a regression between 1.53 to 1.54; if you compile boost/libs/asio/example/cpp11/chat/chat_client.cpp and point it at a host and port that doesn't exist or refuses the connection, instead of coming back with an error, such as host not found or connection refused, it reports success (on the conversion to bool). (you might want to embellish the example with a std::cout << error_code.message() << std::endl;) This appears to be the case across Linux, Darwin, iOS and Android :( synchronous connect seems to work correctly (i.e., echo/blocking_tcp_echo_client.cpp) Ben

2 4

Removing old config macro and increasing compiler requirements.
by Stephen Kelly 12 Sep '13

12 Sep '13

Hi there, I've been working on the modularization effort from a CMake point of view, and from an 'actual modularization' point of view, looking at interdependencies: http://thread.gmane.org/gmane.comp.programming.tools.ryppl.devel/9/focus=26 I'd like to start on reducing interdependencies, and I'd like to start reasonably small, as no-one in the boost community knows me and see how it goes from there. I'm very active in CMake, Qt and KDE. Currently, in the modularized boost repos, boost::config and boost::core depend on each other. I listed 3 ways of fixing this on the ryppl list: http://thread.gmane.org/gmane.comp.programming.tools.ryppl.devel/201 My preference is the removal of BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS, and requiring compilers to have the feature. That way boost/config/suffix.hpp will no longer need to include boost/{non_,}type.hpp. My preference is increasing the compiler requirement, because that may open up more similar opportunities for reducing dependencies and interdependencies throughout boost. Grepping indicates that that means increasing the compiler requirements to something like __DMC__ > 0x840, GCC > 3.2, BOOST_INTEL_CXX_VERSION > 500, VC++ > 7.0. Comments? Thanks, Steve.

15 82

[thread] Can boost::this_thread::sleep_for() totally stop the thread?
by Klaim - Joël Lamotte 03 Sep '13

03 Sep '13

I'm having, sometime, trouble with a rare heisenbug (rare but appearing several times a week). I described it there: http://stackoverflow.com/questions/17918548/can-windows-totally-stop-a-thre… There I ask if it's possible for windows to totally stop a thread that is sleeping too often. As I'm using boost::thread for sleeping this specific thread that, for unknown reason, sometime totally stop working, I'm also wondering if the boost::this_thread() implementation could not be doing something that the OS might not like? ----- I'll report the content of the page here: Can Windows totally stop a thread if it's sleeping too often? I have a rare heisenbug in a multi-threaded application where the main thread, and only this thread, will just do nothing. As it's an heisenbug it's really hard to understand why this is happening. The main thread is basically just looping. In the loop, it check several concurrent priority queues which contain tasks ordered by time to be executed. It pop a task, see if it's time to execute it. If it's time, it will just schedule it into TBB's task scheduler (using a root task which is the parent of all other tasks). If it's not time, the task is pushed again in the priority queue. That's for one cycle. At the end of the cycle, the main thread is put to sleep for a very short time that I expect will be longer in practice but it's not really a problem, I just don't want it to use too much resources when not necessary. Litterally: static const auto TIME_SCHEDULED_TASKS_SPAWN_FREQUENCY = microseconds(250); while( !m_task_scheduler.is_exiting() ) // check if the application should exit { m_clock_scheduler.spawn_realtime_tasks(); // here we spawn tasks if it's time this_thread::sleep_for( TIME_SCHEDULED_TASKS_SPAWN_FREQUENCY ); } m_clock_scheduler.clear_tasks(); m_root_task.wait_for_all(); I have a special task that just log a "TICK" message each second. It is automatically rescheduling until the end of the program. However, when the heisenbug appear, I can see the "TICK" disappearing and the application not doing anything else than the work that occurs in non-main threads. So it appear that only the main thread is touched. The problem can come from different places, maybe in the scheduling logic, but then it's also the only thread that have a sleep call. That sleep is a boost::this_thread::sleep_for(). My question is: **Is it possible that Windows (7 64bit) consider the main thread to be sleeping often and decide that it should sleep for a longer period of time than asked or be definitely ended?** I expect that it is not possible but I would like to be sure. I didn't find any precision on this in online documentation so far. ----- I really suspect that the problem can't come from the sleeping function but I need to eliminate each potential source of problem to isolate it. Thanks for your time. Joel Lamotte

2 9

[multimethods] Proposal: Open Multi-Methods
by Jean-Louis Leroy 01 Sep '13

01 Sep '13

Hi, I am working on library that pretty much implements what Pirkelbauer, Solodkyy and Stroustrup describe in their paper "Open Multi-Methods for C++" - although there are some divergences. I have posted it on GitHub: https://github.com/jll63/multimethods. Please examine the files in the "examples" directory to get an idea of how to use it. Salient features are: * syntax: is relatively uncluttered. There are no limitations on the number of virtual arguments. Virtual and non-virtual arguments can be arbitrarily mixed. Multiple inheritance is supported, with some limitations - see below. * speed: close to a virtual function call when the hierarchies involved in the virtual arguments collaborate with the library. Calling a method that does nothing, with a single virtual argument in a single inheritance hierarchy is 33% slower than the equivalent virtual function call. The difference becomes unnoticeable if the functions perform a few simple maths operations. See tests/benchmarks.cpp. * size: the dispatch table is constructed in terms of class groups. This results, most of the time, in a table devoid of redundancies. The size is bounded by the product of the number of specializers - not classes - in each dimension. * support for "foreign" class hierarchies: the library can be used without modifications to existing classes, at the cost of lower performance. Collaborating and foreign arguments can be freely mixed. Performance is still quite good, see the benchmarks. * next: a pointer to the next most specialized method is available inside method specializations - see examples/next.cpp. Alternatively, it is possible to call a specialization directly. Current limitations are: * restrictions on hierarchy: the classes involved in a method call must have a single root. Repeated inheritance is not supported. Multiple inheritance is supported, provided that the two conditions above are respected. * no overloading: multi-methods are implemented as constexpr function objects. This does not allow for overloading. This restriction can be easily side-stepped by wrapping multi-methods with different names in a set of overloaded functions. I know how to make multi-methods functions instead of objects, at the cost of a slightly less nice syntax for specializers. This is open to discussion. Besides, the library differs from Stroustrup et al's paper on the following points: * a specializer specializes only one multi-method: what would "next" mean otherwise? What would its static type be? * pure multi-methods are allowed: if called, an exception is thrown. This seems a better choice given that most of the time the declared virtual arguments will be abstract classes anyway. The library is essentially feature complete (if anything ever is). I am now going to work on the documentation, a build system, some clean up and compatibility (I tested it only with g++ 4.7.2 only so far). Is there interest in the Boost community for this stuff? If yes, I will adapt it to the guidelines and submit it for formal review. Of course, suggestions are welcome. Thank you for your time, Jean-Louis Leroy

5 10

[type_triats] [move] is_copy_constructible<T> trait
by Antony Polukhin 26 Aug '13

26 Aug '13

Hi, I have an implementation of is_copy_constructible<T> trait. It works great with C++11, in C++03 it detects constructors assuming that if type is derived from boost::noncopyable or uses BOOST_MOVABLE_BUT_NOT_COPYABLE macro - it has no copy constructor. Questions are: * May I add that trait to trunk version of Boost.TypeTraits (with documentation and tests, as usual)? * May I or Boost.Move maintainer apply this patch to BOOST_MOVE_IMPL_NO_COPY_CTOR_OR_ASSIGN in boost/move/core.hpp : #ifdef BOOST_NO_CXX11_DELETED_FUNCTIONS #define BOOST_MOVE_IMPL_NO_COPY_CTOR_OR_ASSIGN(TYPE) \ private:\ TYPE(TYPE &);\ TYPE& operator=(TYPE &);\ + public: \ + typedef int boost_move_no_copy_constructor_or_assign; \ + private: \ // #else Why do I need this trait? Well, it allows to implement move_if_noexcept() that is required for circular_buffer and possibly for other containers. -- Best regards, Antony Polukhin

2 4

Pre-build MSVC Boost binaries
by Fredrik Orderud 13 Aug '13

13 Aug '13

Over the last year, I've set up a small SourceForge "WinBin" project [1] for distributing Microsoft Windows binaries for Boost (and some other projects). The repository is sorted by Boost version, compiler version and shared vs. static linking. Each file archive contains pre-build boost in debug/release for both 32/64-bit, following a include/lib[64]/bin[64] folder structure. There also seems to be some other sources for pre-built boost around (e.g. https://sourceforge.net/projects/boost/files/boost-binaries/ and http://boost.teeks99.com/bin/) However, these do not seem to provide boost built for both static and shared linking. Also, they do not appear to adhere to the "quasi standard" include/lib[64]/bin[64] folder naming convention used by many libraries. Finally, they seem to lack information on which version of python (and possibly other 3rd party SW) they are compiled against. Therefore, I decided to set up my own boost-binaries webpage. Please let me know if you might be interested in either improving the "WinBin" project, or somehow joining forces to merge the various sources of Boost binaries into a single, more "authoritative" repository. I would be more than happy to shut WinBin down if "similar enough" binaries can be downloaded elsewhere. Thanks in advance, Fredrik Orderud [1] https://sourceforge.net/projects/winbin/files/boost/

5 10

Line endings fixes
by Vitaly Budovski 13 Aug '13

13 Aug '13

Hi, Please see the attached files. boost_endings1.patch just sets some of the cpp and other text files to have file endings consistent with the rest of the repository. boost_endings2.patch may be controversial as it does the same but for the svg files. Some of them are marked as text, others as binary. It's a real mess. Most of the svg files are generated from other sources so should probably be omitted from the repository and simply regenerated when docs are built. Came across these issues when checking out the modularised boost git repository. Regards, Vitaly

7 32

[mixin] New library reminder
by Borislav Stanimirov 11 Aug '13

11 Aug '13

Hello, Some of you might remember the previous discussion on the subject (archived here: http://lists.boost.org/Archives/boost/2013/01/200598.php) Anyway, in short, I'm developing a library with the intention to formally submit it to Boost by the end of the year. You can find it here: https://github.com/iboB/boost.mixin The latest news about it is that I think that the library's features for the formal submission are done and all that's left are minor tweaks, bug fixes, tests, examples, and, most importantly, a complete documentation. In the meantime, I again invite you all to check it out. Any comments, suggestions, and questions will be greatly appreciated. Thanks, -- Borislav

3 17

Boost 1.54 build problem: --without-context not honoured?
by Steve M. Robbins 11 Aug '13

11 Aug '13

Hi, I'm digging into a build problem and noticed that even though I specify "./bjam --without-context", Boost.Context is still built! The bjam configuration output states that Context is not to be built: Component configuration: - atomic : building - chrono : building - context : not building - coroutine : building - date_time : building - exception : building But it is built nonetheless. This causes a build failure for architectures which are not supported; see build log [1]. Compare that to the build for 1.53 [2] which works fine. I've diffed the libs/context directory between 1.53 and 1.54 and nothing jumps out at me as the cause. Has anyone noticed and fixed this already? Thanks, -Steve [1] https://buildd.debian.org/status/fetch.php?pkg=boost1.54&arch=ia64&ver=1.54… [2] https://buildd.debian.org/status/fetch.php?pkg=boost1.53&arch=ia64&ver=1.53…

4 4

[boost/spirit] numeric policy
by Brian Schrom 07 Aug '13

07 Aug '13

I've had the case where I needed to retain formatting information for a number (general, fixed, scientific) and was nicely accomplished by extending the policy, but needed to have a begin_parse() and end_parse() for the policy to be complete. It seems that it makes some sense or is this accomplished another way? Maybe something to consider for policies in general? Index: qi/numeric/real_policies.hpp =================================================================== --- qi/numeric/real_policies.hpp (revision 85166) +++ qi/numeric/real_policies.hpp (working copy) @@ -28,6 +28,18 @@ static bool const allow_trailing_dot = true; static bool const expect_dot = false; + template <typename Attribute> + static void + begin_parse(Attribute& attr_) + { + } + + template <typename Attribute> + static void + end_parse(Attribute& attr_,bool /* result */) + { + } + template <typename Iterator> static bool parse_sign(Iterator& /*first*/, Iterator const& /*last*/) Index: qi/numeric/detail/real_impl.hpp =================================================================== --- qi/numeric/detail/real_impl.hpp (revision 85166) +++ qi/numeric/detail/real_impl.hpp (working copy) @@ -133,6 +133,7 @@ parse(Iterator& first, Iterator const& last, Attribute& attr, RealPolicies const& p) { + p.begin_parse(attr); if (first == last) return false; Iterator save = first; @@ -257,6 +258,7 @@ // If we got a negative sign, negate the number traits::assign_to(traits::negate(neg, n), attr); + p.end_parse(attr, true); // maybe this should return a bool and be the return value? // Success!!! return true; }

4 7

[intrusive] Compilation problem with gcc 4.7
by Hartmut Kaiser 07 Aug '13

07 Aug '13

In code which compiled just fine I'm now seeing: In file included from /opt/boost/trunk-debug/boost/intrusive/slist_hook.hpp:24:0, from /opt/boost/trunk-debug/boost/intrusive/slist.hpp:21, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/lcos/local/mu tex.hpp:23, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/runtime/compo nents/server/wrapper_heap.hpp:20, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/runtime/compo nents/server/managed_component_base.hpp:13, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/lcos/base_lco .hpp:12, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/lcos/base_lco _with_value.hpp:11, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/performance_c ounters/counters.hpp:12, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/runtime/compo nents/server/runtime_support.hpp:32, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/hpx/runtime.hpp:1 2, from /opt/buildbot/slave/hpx_gcc47_x8664_boosttrunk_debug/build/src/hpx_main.cpp: 7: /opt/boost/trunk-debug/boost/intrusive/detail/generic_hook.hpp: At global scope: /opt/boost/trunk-debug/boost/intrusive/detail/generic_hook.hpp:134:55: error: declaration of typedef struct boost::intrusive::hooktags<typename GetNodeAlgorithms::type::node_traits, Tag, LinkMode, BaseHookType> boost::intrusive::generic_hook<GetNodeAlgorithms, Tag, LinkMode, BaseHookType>::hooktags [-fpermissive] /opt/boost/trunk-debug/boost/intrusive/detail/generic_hook.hpp:84:8: error: changes meaning of hooktags from struct boost::intrusive::hooktags<typename GetNodeAlgorithms::type::node_traits, Tag, LinkMode, BaseHookType> [-fpermissive] Ion, could you fix this, please? Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

2 2

[move] Documentation example typo.
by Jurko Gospodnetić 04 Aug '13

04 Aug '13

Hi. Just reporting a slight typo in boost::move library documentation's file_descriptor class example code for closing the OS file descriptor. It says: > if(!os_descr_) operating_system_close_file(os_descr_); in its destructor & assignment operator when it should in fact say: > if(os_descr_) operating_system_close_file(os_descr_); [notice the removed ! operator] Hope this helps. Best regards, Jurko Gospodnetić

2 1

[asio] condition_variable for coroutine-powered ASIO
by TONGARI J 04 Aug '13

04 Aug '13

Hi, Since Boost 1.54, ASIO introduced yield_context, which is very helpful to alleviate the pain of writing async ops. Unlike multi-threading, with cooperative multi-tasking, generally we don't have to worry about synchronization, but we still need some sort of mechanism to sync the coroutines in cases like producer-consumer for waiting the data... While I haven't seen any sync tool for asio/coroutine, having a condition_variable or such may be very useful, what do you think? Attached is the poor-man's implementation...

2 1

[utility] [swap] How about Boost.Move?
by Antony Polukhin 03 Aug '13

03 Aug '13

Hi, Sources of Boost.Variant have a swap implementation that takes advantage of move emulation. That code can be useful for Boost.Swap. The idea is not to use std::swap in case of ADL failure, but use a swap implementation that is aware of move emulation: namespace boost_swap_impl { namespace swap_move_emulated { template <typename T> inline void swap(T& lhs, T& rhs) { T tmp( boost::move(lhs) ); lhs = boost::move(rhs); rhs = boost::move(tmp); } } template<class T> void swap_impl(T& left, T& right) { //using namespace std;//use std::swap if argument dependent lookup fails using namespace boost_swap_impl::swap_move_emulated; swap(left,right); } // ... With that code types that use move emulation can be swapped faster and even move only types can be swapped. So, what do the community think about such optimization? -- Best regards, Antony Polukhin

5 8

[git-help] New libraries?
by Rene Rivera 03 Aug '13

03 Aug '13

Today I checked in the new Predef library and I'm wondering, not just for it but in general, if this interim period of svn to git transition what happens to new libraries? Will they automatically show up in the git repos? What are the procedures if the new library is already, originally in git and modularized? Rene. -- -- -- 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

3 5

[predef] FYI..
by Rene Rivera 01 Aug '13

01 Aug '13

FYI.. to those that care.. I checked in changes to SVN to inject the Predef library into Boost. I say inject because the source is not actually in the SVN repo, it's external and still in github. But is being brought in through their SVN interface. Some testers have already runs the tests for it.. And at some point to be determined with some coordination with the community I will switch the "boost/detail/endian.hpp" header to point to the Predef compatibility equivalent... I suspect at the earliest one more week for that assuming no problems surface. Rene. -- -- -- 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

6 10

Re: [boost] [multimethods] Proposal: Open Multi-Methods
by Daryle Walker 01 Aug '13

01 Aug '13

//================================================================= From: Jean-Louis Leroy Sent: ‎Saturday‎, ‎July‎ ‎27‎, ‎2013 ‎8‎:‎26‎ ‎PM I am working on library that pretty much implements what Pirkelbauer, Solodkyy and Stroustrup describe in their paper "Open Multi-Methods for C++" - although there are some divergences. I have posted it on GitHub: https://github.com/jll63/multimethods. Please examine the files in the "examples" directory to get an idea of how to use it. [SNIP] The library is essentially feature complete (if anything ever is). I am now going to work on the documentation, a build system, some clean up and compatibility (I tested it only with g++ 4.7.2 only so far). Is there interest in the Boost community for this stuff? If yes, I will adapt it to the guidelines and submit it for formal review. Of course, suggestions are welcome. //================================================================= Are virtual base classes supported? Maybe “virtual_” should be renamed to “virtualize” or “virtualized,” to avoid having a trailing underscore in a non-member name. A good way to document is to write a Doxygen comment as you write your class, function, or macro prototype. It makes you have to think about what the public side of your code has to do. But looking at your “next.cpp” example, you should start with documenting the “selector,” “virtual_,” “MM_CLASS,” “MM_INIT,” “MULTIMETHOD,” “BEGIN_METHOD,” “END_METHOD,” and “initialize” items. Anything in your implementation classes that don’t have to be seen by public code can be make private. Non-public types can go in a detail namespace. Daryle W.

3 2

[boost thread] Catching interrupted exception?
by Philip Bennefall 31 Jul '13

31 Jul '13

Hi all, I have a quick question regarding the interruption of Boost threads. I am making fairly heavy use of the interrupt method call of the thread class, and I am wondering whether I should be catching the boost::thread_interrupted exception from within my thread function? I currently do not and my program runs fine, but I am wondering whether this is defined behavior or whether I should always be catching the exception and returning from the function inside the handler? Kind regards, Philip Bennefall

2 2

Re: [boost] [asio] Randomly having problems reading from the socket
by Marat Abrarov 30 Jul '13

30 Jul '13

> Posted a Bug Report here: Ticket #8937 > <https://svn.boost.org/trac/boost/ticket/8937> Seems like a bug/feature of Windows 7/Vista (or a bug/feature of Windows socket subsystem) - something in background/foreground process scheduling or a memory management issue. Nevertheless it is interesting to know the Asio author's point of view. It will be more clear if the topic starter rewrites his (simple) examples to use WinSock directly rather than through the Asio (use the same time measurement - by means of boost::posix_time). I think that such rewritten examples will show the same behavior. Regards, Marat Abrarov.

1 0

[preprocessor] ARRAY_REPLACE bug?
by Mostafa 30 Jul '13

30 Jul '13

On Windows 7/Cygwin, using boost 1.53, preprocessing the following snippet: pp_array.cc ----------- #include <boost/preprocessor.hpp> //#define BOOST_PP_TUPLE_REM_0() // nothing #define ARRAY (3, (a, x, c)) BOOST_PP_ARRAY_REPLACE(ARRAY, 1, b) via: g++ -E -P -I /... pp_array.cc gives the following incorrect result: (3, (BOOST_PP_TUPLE_REM_0 () a, b , c)) Uncommenting the pound define in the snippet gives the correct result for the preprocessor. Is this a bug?

3 5

[type_erasure] move
by Christophe Henry 29 Jul '13

29 Jul '13

Hi Steven, I'm looking for a crash I get in my own code with g++4.8.1 (4.5 - 4.7 are ok). Maybe you can help me: - there is a copy_constructible concept, but no moveable. Is it enough to add one on the same model? It looks like you std::forward so I'd say yes. Correct? template<class T = _self> struct move_constructible : ::boost::mpl::vector<constructible<T(T&&)>, destructible<T> > {}; - If I std::move a copy_constructible any type by accident, what do I get? A copy? A crash? Thanks, Christophe

2 2

[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

6 12

New failing tests in circular buffer on some platforms
by Paul A. Bristow 29 Jul '13

29 Jul '13

I note that there are some new failing tests for circular buffer on some platforms http://www.boost.org/development/tests/trunk/developer/circular_buffer.html on MSVC noncopyable_movable_noexcept_t is causing trouble base_test.cpp C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(694) : error C2558: struct 'noncopyable_movable_noexcept_t' : no copy constructor available or copy constructor is declared 'explicit' C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(673) : while compiling class template member function 'noncopyable_movable_noexcept_t *boost::circular_buffer<T>::linearize(void)' with [ T=noncopyable_movable_test_t ] c:\boost_regression\trunk\boost\libs\circular_buffer\test\common.ipp(2160) : see reference to function template instantiation 'noncopyable_movable_noexcept_t *boost::circular_buffer<T>::linearize(void)' being compiled with [ T=noncopyable_movable_test_t ] c:\boost_regression\trunk\boost\libs\circular_buffer\test\common.ipp(2236) : see reference to class template instantiation 'boost::circular_buffer<T>' being compiled with [ T=noncopyable_movable_test_t ] C:\boost_regression\trunk\boost\boost/circular_buffer/base.hpp(697) : error C2558: struct 'noncopyable_movable_noexcept_t' : no copy constructor available or copy constructor is declared 'explicit' ON gcc and Clang there are warnings and failure Running 60 test cases... ../libs/circular_buffer/test/common.ipp(2303): error: in "check_containers_exception_specifications": check boost::has_nothrow_constructor<circular_buffer<int> >::value has failed Can any experts shed light on this? I do not believe that the underlying circular buffer code has changed recently. Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

2 2

[thread] Questions about broken_promise
by Klaim - Joël Lamotte 29 Jul '13

29 Jul '13

I have a few questions concerning broken promises (exception): 1. is the broken_promise exception a standard, or future standard behaviour? So far I assumed it wasn't because http://en.cppreference.com/w/cpp/thread/promise/~promise don't say anything about this and I only read about broken_promise exceptions on Boost.Thread documentation. I would like to know if I should expect the future standard library to have the same concept. I see no configuration macro to deactivate these exceptions. I don't want to actually, but if I'm correct that it's not standard or future standard, then it's surprising that I can't setup a standard-like setup. 2. I have a case that could be summarized like this: ///////////////////////////////////////////// Updated by thread A: struct X { /*... */ }; struct K { future<shared_ptr<X,U>> m_ft_x; shared_ptr<X,U> m_x; K( Foo& foo ) : m_ft_x( foo.create<X>() ) {} void update() // this is always called by a loop in the thread A { if( !m_x ) { if( m_ft_x.has_value() ) m_x = m_ft_x.get(); } else work(); } void work(); // uses m_x }; Updated by thread B: // special deleter which will just push a task in Foo work queue for deleting the object // in sync with thread B struct U { /* ... */ }; struct Foo { template< class T > future<shared_ptr<T,U>> create() // will push a creation task in a work queue updated in update() void update(); // called by a loop in the thread B, will execute all the work pushed in the work queue. }; ///////////////////////////////////////////// (this is an exageratedly simplified version of what I'm doing) It works nicely (even if I think it could be improved with future.then and other tools) but there is a minor problem appearing when an instance of K is constructed then almost immediately destructed, before the instance of Foo executed the creation of the X instance. In this case, visual studio (which is configured to detect all throw calls) detect a broken_promise exception thrown from the destructor of the promise which was in the code generated by Foo::create() and pushed in a work queue. I look at the destructor and I see: if(!future_->done && !future_->is_constructed) { future_->mark_exceptional_finish_internal(boost::copy_exception(broken_promise()), lock); } Here is the full copy_exception code: template <class T> inline exception_ptr copy_exception( T const & e ) { try { throw enable_current_exception(e); } catch( ... ) { return current_exception(); } } This code triggers actually two "first-chance" exceptions this is the first one) which are catch immediately intentionally. My question is: why is copy_exception necessary and why does it have to do it this way? It's a very minor problem as just re-setting my visual studio debugging settings to default makes the exception transparent -only visible in the console log. However each time I activate debug breaking on all c++ exception so that I can debug some potential issues, I can have a breakpoint which is actually "noise" as it is only used to implement a copy of exception. Is it possible to eliminate this noise? Or, as I'm guessing, is there a language or compiler limitation which forces this code to be written this way? Thanks for your time. Joel Lamotte

2 2

safe bool not safe enough ?
by John Maddock 28 Jul '13

28 Jul '13

Just discovered (oops!) that the so called safe bool ideom is not as safe as it appears, for example: class Testable { bool ok_; typedef void (Testable::*bool_type)() const; void this_type_does_not_support_comparisons() const {} public: explicit Testable(bool b=true):ok_(b) {} operator bool_type() const { return ok_==true ? &Testable::this_type_does_not_support_comparisons : 0; } }; Testable t(true); bool b = t; // Compiles OK - Ooops! Which is causing multiprecision to misbehave when used in conjunction with uBlas: https://svn.boost.org/trac/boost/ticket/8292#comment:2 I guess making the conversion explicit in C++11 mode would help (I still need to test that), but is there a C++03 solution? Thanks, John.

4 9

radix sort
by Sourav 28 Jul '13

28 Jul '13

Hi All, I wanted to know if someone is/was working on Radix Sort or not. I did check the SoC listings and did not see radix sort in the list. If no one is working, may someone help me provide some pointers/details as to what the expectation is with regards to Radix sort for boost ? Regards, -Sourav

7 27

boost::python help?
by David M. Cotter 26 Jul '13

26 Jul '13

i'd like my app to be "available" to python while it's running. for example, say my app is "FooBar.app". when my FooBar.app is running, now there is a python interface available to python, and the user can write python scripts to make use of it with their scripts, they can control my running application when FooBar.app is NOT running, perhaps making use of any of the python functions of "FooBar.app" would either return an error, or possibly launch "FooBar.app". can boost::python help with this? i've never worked with extending or embedding python, so any help would be super great

4 5

Patch bonanza for VS2013 Preview support
by Lars Viklund 25 Jul '13

25 Jul '13

Hi list. What's the best way to spend your vacation if not trying to get Boost to build on bleeding-edge compilers. I set out to see how well Boost 1.54.0 behaved on the newly released go-live-ready Visual Studio 2013 Preview. Below is the list of bugs filed against Boost and Microsoft. Enjoy. With these patches in place, I can get a complete build working with all libraries normally available on a fresh machine (means that I didn't test Python, MPI, ICU, compressed streams). I haven't been able to find out how to run the tests in any human-readable form, but this should not cause any regressions as it's either increasing workaround bounds or adding headers that the standard mandates already. Boost.Config VS2013 Preview version bump https://svn.boost.org/trac/boost/ticket/8753 The Visual Studio 2013 Preview toolchain has _MSC_VER 1800 and _MSC_FULL_VER 180020617. See the attached patch for the minimum changes that are needed to get anywhere at all. Boost.Build needs support for the VS2013 Preview toolset (18.00.20617.1) https://svn.boost.org/trac/boost/ticket/8754 Visual Studio 2013 Preview is out and claims to be 12.0. I copy-pasted everything related to 11.0 to refer to 12.0 and it Works On My Machine, see attached patch. Boost.Signals VS2013 Preview version bump https://svn.boost.org/trac/boost/ticket/8755 The BOOST_WORKAROUND macros at boost/signals/detail/named_slot_map.hpp:130 and libs/signals/src/named_slot_map.cpp:27 needs to be increased to <= 1800 in order to encompass the Visual Studio 2013 Preview compiler. Boost.MPL VS2013 Preview version bump https://svn.boost.org/trac/boost/ticket/8756 The BOOST_WORKAROUND macros at boost/mpl/assert.hpp lines 37 and 247 need to be changed to also consider BOOST_MSVC, == 1800, patch attached. Boost.Serialization lacks algorithm header include for std::min https://svn.boost.org/trac/boost/ticket/8757 The <algorithm> header providing std::min is not included in boost/archive/iterators/transform_width.hpp, this breaks on Visual Studio 2013 Preview due to library changes. Boost.Asio lacks algorithm header include for std::min https://svn.boost.org/trac/boost/ticket/8758 The <algorithm> header providing std::min is not included in boost/asio/detail/impl/win_iocp_io_service.hpp, this breaks on Visual Studio 2013 Preview due to library changes. std::bind broken with boost/tuple/tuple.hpp or anything else providing a ADL tie https://connect.microsoft.com/VisualStudio/feedback/details/792163/std-bind… Not our fault, I filed a bug on Connect and am hoping that they'll notice it before RTM. 'std::bind' finds our 'tie' if a type from a boost namespace is used in the 'std::function' argument type list. -- Lars Viklund | zao(a)acc.umu.se

13 35

[preprocessor] ARRAY_REPLACE bug?
by Mostafa 25 Jul '13

25 Jul '13

On Windows 7/Cygwin, using boost 1.53, preprocessing the following snippet: pp_array.cc ----------- #include <boost/preprocessor.hpp> //#define BOOST_PP_TUPLE_REM_0() // nothing #define ARRAY (3, (a, x, c)) BOOST_PP_ARRAY_REPLACE(ARRAY, 1, b) via: g++ -E -P -I /... pp_array.cc gives the following incorrect result: (3, (BOOST_PP_TUPLE_REM_0 () a, b , c)) Uncommenting the pound define in the snippet gives the correct result for the preprocessor. Is this a bug?

1 0

[dynamic_bitset] Compiler intrinsics to accelerate. whos agree?
by Jairo Andres Velasco Romero 25 Jul '13

25 Jul '13

I noted detail for dynamic_bitset<> is not using the far old ASM instruction BSF which could accelerate find_first() and find_next() methodsI checked asm generated with current table based implementation.On x64 and x86 BSF and BSR are available long time ago.Population count can be implemented with LZCNT for performance oriented ways to build.Core i7 with AVX2 enable new wide block bit manipulation but it needs to code with specific GNU g++ intrinsics and MSVC intrinsics. Someone agree? Jairo.

2 1

semi lock-free Signals/Slots
by Andrew Ho 24 Jul '13

24 Jul '13

Hi, I've been doing some testing with implementing a semi lock-free Signals/Slots library. Basically: 1. emits are lock-free thanks to atomic shared_ptr's/other atomic operations. 2. Only a single writer is allowed at a time, uses a mutex for locking. The primary goal is to improve low and no slot-count signal emit performance. In tests, I have been able to get substantial performance boosts (~2 to 5 times) on low slot-count signals, approaching the same performance as signals2 in low-contention (basically, single thread testing). I haven't tested high emit contention performance, though I suspect this library will excel quite well here because there is no locking on emit. The test implementation is still incomplete, and notably uses many C++11 features, though I don't think any of features I'm using can't be ported one way or another for C++03 support. Even if the library isn't used in full, some of the ideas might be implemented into the existing Signals2 library. link: https://github.com/helloworld922/signals3

2 2

Announcing boost dependency analyzer
by Jens Weller 24 Jul '13

24 Jul '13

Hello to the boost community, I'd like to announce the release of a small tool, that allows you analyze the dependencies in boost. It is based on bcp, requirement is that you have bcp build and well a version of boost to analyze installed. Simply select the boost directory (the tool also might find BOOST_ROOT) and the location of bcp, and the tool will start. This will take a little time, depending on your machine, on my multicore intel ist 90 seconds - 2 minute. The tool will store this information into a database, so that with the next start, this will be a lot shorter. The tool allows to analyze the dependcies of a single boost library, but also of all of boost. Its build with Qt for the UI and processing part, and uses boost graph for the layout. Full information + download you'll find at my blogpost: http://www.meetingcpp.com/index.php/br/items/boost-dependency-analyzer.html Current Issues: What libraries might be missing? I'm reading the libs from maintainers.txt, which isn't all the boost libs. For example, lexical_cast is missing, and function_types is twice in there. (C&P error or missing library?) So far Windows is supported, linux support planned and improving, currently ownly the (beta) binaries for linux available. kind regards, Jens Weller

5 9

Re: [boost] [build][msvc] create PDBs
by Ahmed Charles 24 Jul '13

24 Jul '13

The size difference is LTCG, not debug info. ________________________________ From: Daniela Engert Sent: 7/23/2013 9:40 AM To: boost(a)lists.boost.org Subject: Re: [boost] [build][msvc] create PDBs Am 23.07.2013 17:47, schrieb Andrey Semashev: > On Tue, Jul 23, 2013 at 7:39 PM, Daniela Engert <dani(a)ngrt.de> wrote: >> >> libboost_log_setup-vc120-mt-1_54.lib 188.671.120 >> libboost_log_setup-vc120-mt-1_54.pdb 132.616.192 >> libboost_log_setup-vc120-mt-gd-1_54.lib 220.099.308 >> libboost_log_setup-vc120-mt-gd-1_54.pdb 132.837.376 >> libboost_log-vc120-mt-1_54.lib 53.565.446 >> libboost_log-vc120-mt-1_54.pdb 7.942.144 >> libboost_log-vc120-mt-gd-1_54.lib 32.516.250 >> libboost_log-vc120-mt-gd-1_54.pdb 8.114.176 >> > > It looks like static libs contain debug info anyway as they are always > larger than the generated pdb. In many cases, your observed size relationship is true, but not in all of them. E.g.: libboost_exception-vc120-mt-1_54.lib 53.642 libboost_exception-vc120-mt-1_54.pdb 102.400 libboost_exception-vc120-mt-gd-1_54.lib 11.440 libboost_exception-vc120-mt-gd-1_54.pdb 102.400 To exhibit the size advantage of PDBs over 'old-style' debug info embedded into static libs, I've rebuilt Boost.Log with link=static debug-store=object. This is the result: libboost_log_setup-vc120-mt-1_54.lib 343.234.460 libboost_log_setup-vc120-mt-gd-1_54.lib 374.488.888 libboost_log-vc120-mt-1_54.lib 79.564.296 libboost_log-vc120-mt-gd-1_54.lib 59.539.544 Ciao Dani _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

2 1

clang AST based static analysers - Booster's experience
by Niall Douglas 23 Jul '13

23 Jul '13

Dear Boost Devs, I was wondering what the experience of the list is with clang AST based static analysers? They need not be clang AST based of course, so long as they are based on the frontend of a real compiler rather than trying their own implementation based on regex or something even worse. For this list's information, here are the three clang AST based static analysers I know of: 1. Clang's static analyser http://clang-analyzer.llvm.org/ 2. OCLint http://oclint.org/ 3. The commercial tool CppDepend can now use a clang AST (http://blog.llvm.org/2013/04/static-analysis-tools-using-clang-in.html) Some quick notes of mine which may be of dubious accuracy: Clang's static analyser is the more mature tool, but according to http://code.google.com/p/chromium/wiki/ClangStaticAnalyzer which was updated Mar 2013 it feels its default bundled C++ tests is lacking. The real strength in the clang static analyser is for writing your own tests (http://clang-analyzer.llvm.org/checker_dev_manual.html) which enforce specific coding patterns or constraints (usually on others, and usually pre-commit with commit rejection if fail). OCLint is a newer tool, but appears to have fuller support for C++ (http://docs.oclint.org/en/dev/rules/index.html) though many of those rules appear to check C syntax only (which also covers Objective C). Similar to clang's static analyser, new custom rules are easy to write (http://docs.oclint.org/en/dev/internals/rules.html) This project, at least from the outside, seems to have more legs than clang's static analyser. CppDepend I have no experience of, but there is a reasonably positive review at http://www.asawicki.info/news_1511_cppdepend.html. One of the CppDepend developers talks about how they added clang's AST at http://www.codeproject.com/Articles/475254/ClangplusRocks. Niall --- Opinions expressed here are my own and do not necessarily represent those of BlackBerry Inc.

1 0

[build][msvc] create PDBs
by Daniela Engert 23 Jul '13

23 Jul '13

Hi list! For various reasons I always preferred to have debug info separate from the binaries. Unfortunately, emitting debug info to PDBs doesn't work so well, in particular when it comes to static libs and precompiled headers. Because of that I tried to rectify this and created a patch against msvc.jam. (see ticket #8889 https://svn.boost.org/trac/boost/ticket/8889) This (and a tiny script to collect all generated PDBs into the library directory) got me there: boost_log_setup-vc120-mt-1_54.dll 1.158.656 boost_log_setup-vc120-mt-1_54.lib 24.244 boost_log_setup-vc120-mt-1_54.pdb 123.055.104 boost_log_setup-vc120-mt-gd-1_54.dll 3.206.144 boost_log_setup-vc120-mt-gd-1_54.lib 24.408 boost_log_setup-vc120-mt-gd-1_54.pdb 219.220.992 boost_log-vc120-mt-1_54.dll 486.400 boost_log-vc120-mt-1_54.lib 241.174 boost_log-vc120-mt-1_54.pdb 10.857.472 boost_log-vc120-mt-gd-1_54.dll 1.071.616 boost_log-vc120-mt-gd-1_54.lib 242.278 boost_log-vc120-mt-gd-1_54.pdb 18.918.400 libboost_log_setup-vc120-mt-1_54.lib 188.671.120 libboost_log_setup-vc120-mt-1_54.pdb 132.616.192 libboost_log_setup-vc120-mt-gd-1_54.lib 220.099.308 libboost_log_setup-vc120-mt-gd-1_54.pdb 132.837.376 libboost_log-vc120-mt-1_54.lib 53.565.446 libboost_log-vc120-mt-1_54.pdb 7.942.144 libboost_log-vc120-mt-gd-1_54.lib 32.516.250 libboost_log-vc120-mt-gd-1_54.pdb 8.114.176 Boost.Log was chosen for exhibition only. All files were built with debug-symbols=on debug-store=database. Link-time code generation was enabled for all release builds, too. May be, someone finds this helpful. Ciao Dani

2 2

[format] doc fix
by Tim Blechmann 23 Jul '13

23 Jul '13

not sure, how well-maintained boost.format is these days ... any objection if i commit this documentation fix? cheers, tim

1 0

Fwd: Re: Announcing boost dependency analyzer
by Stephen Kelly 23 Jul '13

23 Jul '13

Jens Weller wrote: >> Unfortunately the Boost dependency graph is as huge a hairball as I was >> afraid :-/ > > Hi, thanks for the feedback. Yes, dependency graph for boost is quite > large... I think with boost in git and modules available, this is going to > improve. That won't happen automatically. The git conversion is separate to reorganizing to resolve the solvable interdepency issues: http://thread.gmane.org/gmane.comp.programming.tools.ryppl.devel/201/focus=… The salient point is: > By modularizing and making the interdependencies explicit, we hope to > encourage developers to refactor. But we can only solve one problem at a > time. So, if you want to work on resolving interdependencies, don't wait for the git conversion to be done, because it won't help, and do pick up your editor and dig, because only that will help. Thanks, Steve.

1 0

Regression tests report page cycling slow
by Joaquin M Lopez Munoz 23 Jul '13

23 Jul '13

Hi, the page http://www.boost.org/development/tests/trunk/developer/summary.html seems to update very unfrequently, every two days or longer. Can something be done to speed this up? Thank you in advance, Joaquín M López Muñoz Telefónica Digital

2 1

Requesting number crunchers for trial complex classes
by Daryle Walker 22 Jul '13

22 Jul '13

I just pushed out commit "aaeabbd3fcc04956c4fd3d3825f6202355ab9297" of my trial hypercomplex number classes at https://github.com/CTMacUser/Complex. The classes now have all the arithmetic operators. They already have the condition functions (norm and conj), norm functions (taxi (ex L1), abs, sup, and sgn), and equality operators. There is an output operator, but not input. There are constructors for: default (both garbage bits and all zeros), copy and move (automatically defined), component (single or list), cross version, smaller hypercomplex (single and list), and (head of) larger hypercomplex. Look at the unit tests for usage examples. I haven't done any utility or transcendental functions yet, so let me know if you need them before proceeding. I just want people who do hard-core number crunching with complex, quaternion, and/or octonion numbers to see if my classes are worth it, performance-wise. You can also use the array-of-hypercomplex to array-of-many-reals reinterpret_cast trick. Everything should have Doxygen comments. I run this code on GCC 4.7.1 off MinGW for 32-bit Windows 8 Pro, so tests on other compilers will be appreciated. (It probably can't run on Visual C++, but GCC 4.8 and Clang 3.x will probably work.) Note on octonions: a month ago I found out, while looking for online octonion calculators, that octonion (and above) multiplication isn't standardized. I'm using the same philosophy from Wikipedia, which is also used by the existing Boost.Octonion. (Actually, I found a bug in B.O.'s octonion times quaternion code, since that author manually lists all the sub-terms, and my code is more automatic. I had to do the multiplication by hand to check who had it right.) So if your octonion products are different, it may not be a bug. I've tried to make as many constructors/operators/functions constexpr as possible. (That's why no std::initializer_list.) That may help move data into ROM, but you have to force non-inline-ness when you need to test runtime performance. Daryle W.

1 0

[Locale] does generator("") deliver the system's default locale?
by Michael Schinner 22 Jul '13

22 Jul '13

boost 1.54.0 When I use boost::locale::generator and generator("") I get different results for the decimal point than using std::locale(""). Boths methods are supposted to deliver the system's default locale. Example: // windows 7, de_AT std::use_facet<std::numpunct<char> >(std::locale("")).decimal_point(); // delivers a , boost::locale::generator generator; std::use_facet<std::numpunct<char> >(generator("")).decimal_point(); // delivers a . What does generator("")) deliver? Is it wanted that a '.' is deliverd as decimal point for a german locale? Best regards, Michael

2 1

[system] Do we need this library with latest (almost C++0x) compilers?
by Tonko Juricic 22 Jul '13

22 Jul '13

Can somebody please explain what is missing in current compiler implementations? What is preventing other libraries to have a macro like: #ifdef _CPP11_THREAD_ #include <thread> #include <mutex> #include <condition_variable> #else #include <boost/thread.hpp> #include <boost/thread/mutex.hpp> #include <boost/thread/condition_variable.hpp> #endif also when it comes to error codes and conditions? Thanks, Tony

3 2

windows_shared_memory - does memory block exists?
by piotr.ns 21 Jul '13

21 Jul '13

Hi, Why native windows shared memory does not include any means to check for existance of memory block without throwing exceptions? A small function would be enough: // boost::interprocess::windows_shared_memory static bool exists(const std::string &a_path) { using namespace boost::interprocess; try { unsigned long file_map_access = winapi::page_readonly; unsigned long map_access = winapi::file_map_read; void *test_handle = winapi::open_file_mapping(map_access, a_path.c_str()); bool res = (test_handle != NULL); if(res) winapi::close_handle(test_handle); return res; } catch(...) { return false; } } Without this I have to use Boost internals (winapi::*) in my application. Would somebody consider including this code or something similar? Regards, Piotr

1 0

Status of various Boost initiatives?
by Robert Ramey 21 Jul '13

21 Jul '13

I'm trying to get a handle on the current state of the various boost migrations which have been underway. a) migration to GIT b) migration to CMake c) status of rypll when I try to track this down I find many dead links, repeated information. I also don't find some blogs I used to be able to find on these subjects. Anyone up to provide an current status snapshot? Robert Ramey

5 14

Mag Gam
by Mag Gam 21 Jul '13

21 Jul '13

http://yumaonline.it/bau/bcjk.xvdhjqpdiniqwmxf Mag Gam 7/21/2013 7:26:51 AM

1 0

Re: [boost] [regression] patch for running tests in parallel and out-of-sync files
by Robert Kawulak 20 Jul '13

20 Jul '13

> From: Robert Kawulak > When I was running tests in parallel (using b2 -j option) I was getting random > warnings in the results table because "msvc.manifest" lines were interleaved with > compile/link actions. I've fixed this with the attached patch - is it OK to apply > it to trunk/release? Due to the lack of feedback I've gone ahead and applied the fix in trunk for now. If nobody objects or reports issues, I'll merge it into release later. > BTW, I've noticed that the following files in tools/regression/src haven't been > updated in release branch even though they've been changed in trunk a long time > ago: > compiler_status.cpp (trunk date 2012-01-21, release date 2011-10-06) > library_status.cpp (trunk date 2013-03-25, release date 2013-03-09) > Is it OK to update these in release branch? Likewise, I've updated the two files in release. I've also added tools/regression/build/bin directory to ignore list (it's created when invoking b2 from tools). Best regards, Robert

1 0

[git conversion] type_traits problems; spurious headers
by Beman Dawes 20 Jul '13

20 Jul '13

libs/type_traits/include/boost has these files: aligned_storage.hpp call_traits.hpp config.hpp smart_ptr.hpp timer.hpp type_traits.hpp utility.hpp AFAIK, call_traits.hpp and type_traits.hpp are supposed to be there, but the rest are spurious, and are causing "b2 headers" to create some incorrect links that are preventing testing many libraries. --Beman

2 1

[git-help] Status?
by Rene Rivera 20 Jul '13

20 Jul '13

I started looking at making the final minor set of changes to the regression testing scripts to have the option of testing the modular git version of the boost super-project. Unfortunately it now seems that the super-project no longer has *any* of the references to the library sub-projects. Me not being able to get this work done now is rather annoying as it likely means that the testing will not be ready early in the 1.55 release cycle. Which is the release currently scheduled to switch to git. What is the status of the git transition? When will the Boost release team be able to start working on the switch? Rene. -- -- -- 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

5 11

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.

7 8

Boost Mingw w64 compilation issues and fixes
by Andrew Ho 19 Jul '13

19 Jul '13

Hi, I've been working on getting Boost to compile properly with Mingw w64 on Windows x64 (specifically, Mingw w64 with GCC 4.8.1 rev 2/Windows threads, http://sourceforge.net/projects/mingwbuilds/files/host- windows/releases/4.8.1/64-bit/threads-win32/seh/). Link to trac bug reports/patches: Boost config/Boost thread: https://svn.boost.org/trac/boost/ticket/8817 I believe this fix works with all target platforms, though I can't test with Windows CE to verify that it works. At least works with VS2012 and Mingw w64. Boost Python: https://svn.boost.org/trac/boost/ticket/8818 This fix again works with VS2012 and Mingw w64. It moves an #undef hypot directive (which python.h unfortunately uses) to be used any time python.h decides it needs to define it. I don't know if any platforms/compilers rely on having hypot being defined as a macro. Doesn't link for me because I think the official Windows Python release is built with VS, I'll need to find/build Python with Mingw w64 to see if it works. Boost Log: https://svn.boost.org/trac/boost/ticket/8819 (apparently has already been reported as https://svn.boost.org/trac/boost/ticket/8786) Boost Math: TBD There is some compile error with Boost Math which is causing my compiler to crash. I don't know if this is on the Boost Math side, or is a bug with Mingw w64. I'll submit a bug report and possibly a patch when I have a bit more time to dig into the issue. I think these are the main outstanding issues with getting Boost to compile with Mingw w64 on x64 Windows. I was able to get everything else to compile smoothly with Mingw w64 and VS2012 (targeting x64).

3 9

invalid "this is an old version of boost" links
by Mathieu Champlon 19 Jul '13

19 Jul '13

Hi, All the links at the top of documentation pages for previous versions of boost seem to have suddenly become invalid as they all link to http://www.boost.org/doc/libs/ For instance see http://www.boost.org/doc/libs/1_48_0/libs/config/doc/html/boost_config/boos… I cannot remember when I first noticed it, maybe a couple of weeks ago. Cheers, MAT.

2 1

[serialization][static_assert] Moving BOOST_STATIC_WARNING to Boost.StaticAssert?
by Petr Machata 19 Jul '13

19 Jul '13

Hi there, do you think it would make sense to move static_warning.hpp from boost/serialization up directly under boost/, and perhaps move it conceptually under Boost.StaticAssert umbrella? It seems strange how a serialization library exposes such general-purpose service. We could still provide a forwarding header in Serialization namespace for backward compatibility. Shall I prepare a patch to that effect? Thanks, PM

2 3

[git] creating symlinks in the git layout
by Beman Dawes 19 Jul '13

19 Jul '13

Steven added "Initial supprort for creating symlinks in the git layout" in changeset 84524. How is this support used? Is it working reliably? Thanks, --Beman

2 2

[bitstream] Copy stream buffer or pass pointer?
by Paul Long 18 Jul '13

18 Jul '13

While working on a bitstream library I proposed a while back (http://article.gmane.org/gmane.comp.lib.boost.devel/242574) I came across a design decision for which I'd like to get some feedback. The proposed bitstream library (https://github.com/dplong/bitstream) mimics the std::stringstream class hierarchy and semantics as close as possible. In general, when the consumer of the std::stringstream/stringbuf classes provides a string for the stream buffer, a copy gets made; likewise, when it retrieves the stream buffer, it gets a copy of the string. For example, the following snippet prints "hello, goodbye". char c[BUFSIZ] = "hello"; istringstream iss(c); strcpy(c, "goodbye"); cout << iss.str() << ", " << c; However, the library I'm working on doesn't copy. Instead, pointers are passed in and out. So, for example, this code prints "goodbye, goodbye". char c[BUFSIZ] = "hello"; ibitstream ibs(c); strcpy(c, "goodbye"); cout << ibs.data() << ", " << c; I don't think either way is more correct than the other. The reason I don't copy is for memory and CPU performance, thinking that the streams a bit-stream library typically processes are larger than the streams that a string-stream library processes and are more time critical. I very well may be mistaken, though. Anyway, what do you people think? Copy or don't copy? Maybe I should do copies just to follow the semantics of std::stringstream. Oh, also, am I being presumptuous by including "[bitstream]" in the Subject header of this post since it's just a _proposed_ library? IOW, should I stop doing that? Paul

3 3

[build] bootstrap.sh is triply broken on MinGW
by Stephan T. Lavavej 18 Jul '13

18 Jul '13

Hi, For over a year I've been suffering from bootstrap.sh being broken on MinGW, although I figured out a horrible hackaround. In 1.54.0 two more breaks appeared, and I figured out real fixes for them. I'd like to offer my real fixes here, and request two things: (A) a real fix to replace my horrible hackaround for the original bug, and (B) bootstrap.sh to be tested on MinGW for each release, because it's clearly not receiving sufficient coverage. The first break appears to be tracked by https://svn.boost.org/trac/boost/ticket/5680 and https://svn.boost.org/trac/boost/ticket/6350 . The problem is that bootstrap.sh and b2.exe don't agree on what MinGW should be called: is it mingw or is it gcc? No permutations of toolsets passed on the command lines work. I've used the following horrible hackaround in 1.49.0 through 1.54.0 inclusive: diff -aurN boost_1_54_0/bootstrap.sh boost_1_54_0-fixed/bootstrap.sh --- boost_1_54_0/bootstrap.sh 2013-03-09 14:55:05 -0800 +++ boost_1_54_0-fixed/bootstrap.sh 2013-07-18 00:12:38 -0700 @@ -215,7 +215,7 @@ if test "x$BJAM" = x; then echo -n "Building Boost.Build engine with toolset $TOOLSET... " pwd=`pwd` - (cd "$my_dir/tools/build/v2/engine" && ./build.sh "$TOOLSET") > bootstrap.log 2>&1 + (cd "$my_dir/tools/build/v2/engine" && ./build.sh mingw) > bootstrap.log 2>&1 if [ $? -ne 0 ]; then echo echo "Failed to build Boost.Build build engine" Of course, this is completely unacceptable for other toolsets, but I basically know nothing about Boost's build machinery, so I can't figure out a real fix. Ideally, bootstrap.sh followed by b2.exe would work automatically, without toolsets being specified. However, I would still be extremely happy if it worked with manually specified toolsets, as long as I didn't have to patch or sed files. The second and third breaks are new to 1.54.0 and are tracked by https://svn.boost.org/trac/boost/ticket/8762 . Here are my fixes that should work for all platforms: diff -aurN boost_1_54_0/tools/build/v2/engine/build.jam boost_1_54_0-fixed/tools/build/v2/engine/build.jam --- boost_1_54_0/tools/build/v2/engine/build.jam 2013-05-20 21:14:18 -0700 +++ boost_1_54_0-fixed/tools/build/v2/engine/build.jam 2013-07-18 00:12:43 -0700 @@ -483,8 +483,8 @@ make.c make1.c mem.c object.c option.c output.c parse.c pathsys.c regexp.c rules.c scan.c search.c subst.c w32_getreg.c timestamp.c variable.c modules.c strings.c filesys.c builtins.c class.c cwd.c native.c md5.c - modules/set.c modules/path.c modules/regex.c modules/property-set.c - modules/sequence.c modules/order.c ; + [ .path modules set.c ] [ .path modules path.c ] [ .path modules regex.c ] + [ .path modules property-set.c ] [ .path modules sequence.c ] [ .path modules order.c ] ; if $(OS) = NT { jam.source += execnt.c filent.c pathnt.c ; It appears that build.jam needs to use this .path machinery to generate either forward slashes or backslashes. When forward slashes are literally used, the bootstrap complains that it doesn't know how to make the corresponding object files. Once this is fixed, the final break is revealed: diff -aurN boost_1_54_0/tools/build/v2/engine/build.sh boost_1_54_0-fixed/tools/build/v2/engine/build.sh --- boost_1_54_0/tools/build/v2/engine/build.sh 2013-05-20 21:14:18 -0700 +++ boost_1_54_0-fixed/tools/build/v2/engine/build.sh 2013-07-18 00:12:43 -0700 @@ -247,18 +247,18 @@ BJAM_SOURCES="\ command.c compile.c constants.c debug.c execcmd.c frames.c function.c glob.c\ hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c\ - object.c option.c output.c parse.c pathsys.c pathunix.c regexp.c rules.c\ + object.c option.c output.c parse.c pathsys.c regexp.c rules.c\ scan.c search.c subst.c timestamp.c variable.c modules.c strings.c filesys.c\ builtins.c class.c cwd.c native.c md5.c w32_getreg.c modules/set.c\ modules/path.c modules/regex.c modules/property-set.c modules/sequence.c\ modules/order.c" case $BOOST_JAM_TOOLSET in mingw) - BJAM_SOURCES="${BJAM_SOURCES} execnt.c filent.c" + BJAM_SOURCES="${BJAM_SOURCES} execnt.c filent.c pathnt.c" ;; *) - BJAM_SOURCES="${BJAM_SOURCES} execunix.c fileunix.c" + BJAM_SOURCES="${BJAM_SOURCES} execunix.c fileunix.c pathunix.c" ;; esac (It took me quite some time to figure out this one.) Although pathunix.c compiles on MinGW, it doesn't work, causing the bootstrap to complain about not being able to write its command file. The correct pattern to follow (as correctly done in build.jam; you can see half of it at the bottom of the build.jam diff here) is for pathnt.c to be used for mingw and pathunix.c to be used for all other build.sh platforms (i.e. real Unixes). Thanks, Stephan T. Lavavej

1 0

[container][set, map, flat_set, flat_map, +multi_xxx] operator< and operator== seems to ignore custom KeyCompare
by Thorsten Ottosen 18 Jul '13

18 Jul '13

Hi Ion & others, I think that there might be a problem in the implementation of operator< for these containers. There might be a problem with operator== too. The problem is that they all use some variant of the following definition: template <class Key, class Value, class KeyOfValue, class KeyCompare, class A> inline bool operator<(const rbtree<Key,Value,KeyOfValue,KeyCompare,A>& x, const rbtree<Key,Value,KeyOfValue,KeyCompare,A>& y) { return std::lexicographical_compare(x.begin(), x.end(), y.begin(), y.end()); } There is no KeyCompare (or other compare object) passsed to lexicographical compare. Reading up on the standard, it seems that all standard containers are implemented this way. Consequence: when having e.g. set<T*>, the comparison is not portable, since only std::less<T*> is guaranteed to be. So isn't this a defect? The other issue is perhaps more sensitive. What should users expect from typedef set<std::string,CaseInsensitiveLess> Set; Set s1{ "foo", "BAR" }; Set s2{ "FOO", "bar" }; assert( s1 < s2 ); // true? assert( s1 == s2 ); // true? I was at least surprised by this behavior. regards Thorsten

3 4

Git Modularization example Boost .gitattributes
by Niall Douglas 16 Jul '13

16 Jul '13

> > Shouldn't the repositories contain a .gitattributes file indicating the > > eol flavor to be used for text files where it has significance? > > Perhaps! I don't know anything about .gitattributes. Where can I find > out more? Dave, I can probably save you some work here with my "perfect" mirror of Boost's EOL and MIME type config into a .gitattributes with which I configured my subgit to mirror my git repo into Boost sandbox. Taken from https://github.com/ned14/TripleGit/blob/master/.gitattributes: * text=auto !eol svneol=native#text/plain *.gitattributes text svneol=native#text/plain # Scriptish formats *.bat text svneol=native#text/plain *.bsh text svneol=native#text/x-beanshell *.cgi text svneol=native#text/plain *.cmd text svneol=native#text/plain *.js text svneol=native#text/javascript *.php text svneol=native#text/x-php *.pl text svneol=native#text/x-perl *.pm text svneol=native#text/x-perl *.py text svneol=native#text/x-python *.sh eol=lf svneol=LF#text/x-sh configure eol=lf svneol=LF#text/x-sh # Image formats *.bmp binary svneol=unset#image/bmp *.gif binary svneol=unset#image/gif *.ico binary svneol=unset#image/ico *.jpeg binary svneol=unset#image/jpeg *.jpg binary svneol=unset#image/jpeg *.png binary svneol=unset#image/png *.tif binary svneol=unset#image/tiff *.tiff binary svneol=unset#image/tiff *.svg text svneol=native#image/svg%2Bxml # Data formats *.pdf binary svneol=unset#application/pdf *.avi binary svneol=unset#video/avi *.doc binary svneol=unset#application/msword *.dsp text svneol=crlf#text/plain *.dsw text svneol=crlf#text/plain *.eps binary svneol=unset#application/postscript *.gz binary svneol=unset#application/gzip *.mov binary svneol=unset#video/quicktime *.mp3 binary svneol=unset#audio/mpeg *.ppt binary svneol=unset#application/vnd.ms-powerpoint *.ps binary svneol=unset#application/postscript *.psd binary svneol=unset#application/photoshop *.rdf binary svneol=unset#text/rdf *.rss text svneol=unset#text/xml *.rtf binary svneol=unset#text/rtf *.sln text svneol=native#text/plain *.swf binary svneol=unset#application/x-shockwave-flash *.tgz binary svneol=unset#application/gzip *.vcproj text svneol=native#text/xml *.vcxproj text svneol=native#text/xml *.vsprops text svneol=native#text/xml *.wav binary svneol=unset#audio/wav *.xls binary svneol=unset#application/vnd.ms-excel *.zip binary svneol=unset#application/zip # Text formats .htaccess text svneol=native#text/plain *.bbk text svneol=native#text/xml *.cmake text svneol=native#text/plain *.css text svneol=native#text/css *.dtd text svneol=native#text/xml *.htm text svneol=native#text/html *.html text svneol=native#text/html *.ini text svneol=native#text/plain *.log text svneol=native#text/plain *.mak text svneol=native#text/plain *.qbk text svneol=native#text/plain *.rst text svneol=native#text/plain *.sql text svneol=native#text/x-sql *.txt text svneol=native#text/plain *.xhtml text svneol=native#text/xhtml%2Bxml *.xml text svneol=native#text/xml *.xsd text svneol=native#text/xml *.xsl text svneol=native#text/xml *.xslt text svneol=native#text/xml *.xul text svneol=native#text/xul *.yml text svneol=native#text/plain boost-no-inspect text svneol=native#text/plain CHANGES text svneol=native#text/plain COPYING text svneol=native#text/plain INSTALL text svneol=native#text/plain Jamfile text svneol=native#text/plain Jamroot text svneol=native#text/plain Jamfile.v2 text svneol=native#text/plain Jamrules text svneol=native#text/plain Makefile* text svneol=native#text/plain README text svneol=native#text/plain TODO text svneol=native#text/plain # Code formats *.c text svneol=native#text/plain *.cpp text svneol=native#text/plain *.h text svneol=native#text/plain *.hpp text svneol=native#text/plain *.ipp text svneol=native#text/plain *.tpp text svneol=native#text/plain *.jam text svneol=native#text/plain *.java text svneol=native#text/plain Hope that's useful. Niall --- Opinions expressed here are my own and do not necessarily represent those of BlackBerry Inc.

2 4

detail/endian.hpp replacement?
by Philip Bennefall 15 Jul '13

15 Jul '13

Hi all, I just wanted to ask about the possibility of getting the Boost licensed fix for detail/endian.hpp into the next release of Boost? It would be great to have that license ambiguity resolved for version 1.55.0. Kind regards, Philip Bennefall

2 2

[thread] Is future.then( scheduler , task ) abandoned?
by Klaim - Joël Lamotte 15 Jul '13

15 Jul '13

On this page: http://www.boost.org/doc/libs/1_54_0/doc/html/thread/future.html And in the task list: https://svn.boost.org/trac/boost/query?status=!closed&component=thread We can see that there are plans to add async( scheduler, task ). However there are no tasks for future.then( scheduler, task ). The documentation suggests that it will be implemented in a future release. So I just wanted a confirmation: is it still planned or is it abandoned? Or is it just a missing task? Joel Lamotte

2 2

Git Modularization hiccups
by Beman Dawes 15 Jul '13

15 Jul '13

* "git clone --recursive http://github.com/boostorg/boost modular-boost" is mostly working fine here (on Win7) but is producing one set of error messages: Cloning into 'libs/assign'... fatal: reference is not a tree: 57ec5d1534810090649b18c88e66a46f48cdcf1c ... Unable to checkout '57ec5d1534810090649b18c88e66a46f48cdcf1c' in submodule path 'libs/assign' The remaining hiccups are in the root directory, comparing trunk to master: * boost.css is missing content from revisions 36243 and 53553. * boost-build.jam has different comments and history. Something is totally whacky. * boostcpp.py contents are the same, but the trunk file has Unix line endings, the master file has Windows line endings. * Same problem with bootstrap.sh. IIRC, it is important that the .sh files have the Unix line endings. * c++boost.gif not present in trunk, present in master. * index.html missing in master. * Jamfile.v2 and Jamroot.jam not present in trunk, present in master. * INSTALL missing in master. * LICENSE_1_0.txt has Unix line endings in trunk, Windows line endings in master. * project-config.jam missing in master. * rst.cc missing in master. * README.txt not present in trunk, present in master. HTH, --Beman

9 17

Release branch now open for merging
by Marshall Clow 15 Jul '13

15 Jul '13

The release branch (https://svn.boost.org/svn/boost/branches/release) is open for merging all stable changes from trunk, including bug fixes and major upgrades to existing libraries. Breaking changes should be coordinated via the mailing list with the developers of the other libraries affected. New libraries may be added, but require permission of a release manager. In other words, merging *does not* require permission from a release manager, except for new libraries. Boost Calendar with the release schedule: http://www.boost.org/development/index.html Release schedule explanation: http://svn.boost.org/trac/boost/wiki/ReleaseSchedule Release practices for developers: http://svn.boost.org/trac/boost/wiki/ImprovingPractices -- The Release Managers, Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

1 0

[function] type conversion ambiguity?
by Andrew Ho 15 Jul '13

15 Jul '13

Consider the overloaded functions foo and bar: typedef boost::function<void(void)> function_type1; typedef boost::function<void(int)> function_type2; typedef std::function<void(void)> function_type3; typedef std::function<void(int)> function_type4; void foo(const function_type1 &a) { // blah } void foo(const function_type2 &a) { // blah } void bar(const function_type3 &a) { // blah } void bar(const function_type4 &a) { // blah } calling foo with a function pointer is ambiguous, but calling bar is not: void doit1(void) {} void doit2(int) {} foo(&doit1); // ambiguous bar(&doit2); // compiles and runs fine This occurs despite the fact that boost::function<void(void)>(&doit2) can be caught at compile time. Is there some way to fix the definition of boost::function such that this is no longer ambiguous?

2 1

Nullable types
by Bjorn Reese 15 Jul '13

15 Jul '13

It seems like different Boost libraries use different nullable types. * Optional uses boost::none * Tribool uses boost::logic::indeterminate_keyword_t * Tuple uses boost::tuples::null_type * Variant uses boost::blank And there are possibly more. What are your opinions about unifying these?

4 3

Extremely large Visual Studio libboost_log_setup* binaries
by Tom Kent 14 Jul '13

14 Jul '13

In the 1.54.0 release, I noticed that the size of the binaries built with visual studio was more than twice that of the previous releases. For example the msvc-8.0-64 build went from 2GB to 5GB. Upon further investigation, almost all of that increase was in the libboost_log_setup* binaries, which were each in the 100s of MBs. Does anyone know if there is a reason for this? Is it a configuration error? Tom Kent

8 22

Boost.Operators and make_shared
by Pieter 13 Jul '13

13 Jul '13

LS, I have noticed that using Boost.Operators has a side-effect which I can't explain. I am using std::make_shared as a default, however, some of the boost libraries I use pull in boost::make_shared as well. When using some class T2 derived from one of the boost.operators classes, this causes MSVC2010 to not compile when invoking make_shared<T2> as the compiler can no longer resolve between the two overloaded versions of make_shared for some reason. I am hoping that someone out can explain what is happening here. A minimal example is included here: #include <memory> #include <boost\operators.hpp> #include <boost\make_shared.hpp> struct T1 {}; struct T2 : boost::equality_comparable<T2> {}; int main( int argc, const char* argv[] ) { T1 Object1; T2 Object2; using std::make_shared; std::shared_ptr<T1> Ptr1 = make_shared<T1>(Object1); // OK std::shared_ptr<T2> Ptr2 = make_shared<T2>(Object2); // error C2668: 'boost::make_shared' : ambiguous call to overloaded function return 1; } Thanks in advance! Pieter

4 6

[regression] patch for running tests in parallel and out-of-sync files
by Robert Kawulak 13 Jul '13

13 Jul '13

When I was running tests in parallel (using b2 -j option) I was getting random warnings in the results table because "msvc.manifest" lines were interleaved with compile/link actions. I've fixed this with the attached patch - is it OK to apply it to trunk/release? BTW, I've noticed that the following files in tools/regression/src haven't been updated in release branch even though they've been changed in trunk a long time ago: compiler_status.cpp (trunk date 2012-01-21, release date 2011-10-06) library_status.cpp (trunk date 2013-03-25, release date 2013-03-09) Is it OK to update these in release branch? Best regards, Robert

1 0

[log] Set default log source name
by Renato Forti 12 Jul '13

12 Jul '13

Hi All, Have any way to define a custon log source name on simple_event_log_backend! I foud a method to get (get_default_source_name), but where is "set" method! HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\Application\do kagent simple event source I want set/change default name (in my case) : "dokagent simple event source" Thanks

2 1

[config] Feature request: BOOST_OVERRIDE
by Borislav Stanimirov 12 Jul '13

12 Jul '13

Hi, I think it will be a nice feature to add BOOST_OVERRIDE to Boost.Config in a manner similar to BOOST_CONSTEXPR. It's a nice keyword and it would be nice if people could make use of it when it's available. -- Borislav

5 4

multi_index broken on gcc4.7
by Hartmut Kaiser 12 Jul '13

12 Jul '13

In code which compiled just fine until yesterday I'm now seeing: /opt/boost/trunk-release/boost/multi_index/detail/index_base.hpp: In member function 'std::pair<typename boost::multi_index::detail::multi_index_node_type<Value, IndexSpecifierList, Allocator>::type*, bool> boost::multi_index::detail::index_base<Value, IndexSpecifierList, Allocator>::final_emplace_(Args&& ...)': /opt/boost/trunk-release/boost/multi_index/detail/index_base.hpp:214:29: error: expected primary-expression before ')' token /opt/boost/trunk-release/boost/multi_index/detail/index_base.hpp: In member function 'std::pair<typename boost::multi_index::detail::multi_index_node_type<Value, IndexSpecifierList, Allocator>::type*, bool> boost::multi_index::detail::index_base<Value, IndexSpecifierList, Allocator>::final_emplace_hint_(boost::multi_index::detail::index_base<Value , IndexSpecifierList, Allocator>::final_node_type*, Args&& ...)': /opt/boost/trunk-release/boost/multi_index/detail/index_base.hpp:233:16: error: expected primary-expression before ')' token OS: Debian Unstable Kernel: Linux 3.2 GCC: 4.7 (C++11, x86-64) Boost: SVN Trunk Build Type: Release Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

2 2

[variant] Applying a portion of fixes
by Antony Polukhin 12 Jul '13

12 Jul '13

Hi, I'd like to fix this issue: https://svn.boost.org/trac/boost/ticket/8772 Apply patch for this issue: https://svn.boost.org/trac/boost/ticket/7911 And take care of this: https://svn.boost.org/trac/boost/ticket/8717 Patches and ideas for fixes are described in tickets. If there'll be no objections till next weekend I'll commit the fixes. -- Best regards, Antony Polukhin

1 0

Boost 1.54.0 released!
by Marshall Clow 11 Jul '13

11 Jul '13

Release 1.54.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains five new libraries and numerous enhancements and bug fixes for existing libraries. New Libraries: Log: Logging library, from Andrey Semashev. TTI: Type Traits Introspection library, from Edward Diener. Type Erasure: Runtime polymorphism based on concepts. For details, including download links, see http://www.boost.org/users/news/version_1.54.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.54.0/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

5 9

Regression tests report page stuck
by Joaquin M Lopez Munoz 11 Jul '13

11 Jul '13

Hi, the trunk testing bot http://www.boost.org/development/tests/trunk/developer/summary.html seems to be stuck since ~1.5 days ago. Thank you, Joaquín M López Muñoz Telefónica Digital

1 1

[gil] Portability of new code issue.
by Harg Tholan 11 Jul '13

11 Jul '13

Hi all, Christian has been working on some new features for GIL, such code works fine in Windows 7 with VS11, but it will fail to compile with GCC in Debian Wheezy. I've been trying to figure out why is this failing and possible workarounds with no success. For those with time wanting to help: 1. You will need boost-trunk. 2. I have attached the "bleeding edge" code (a pair of .hpp) as well as a test case. 3. Compile: g++ subsampled_test.cpp -o ss -lboost_unittesting_framework My Compiler Version: g++ (Debian 4.7.2-5) 4.7.2 Errors: yuv_image.hpp:234:38: error: expected primary-expression before ‘,’ token subsampled_test.cpp:28:41: required from here ../yuv_image.hpp:234:5: error: ISO C++ forbids comparison between pointer and integer Note: I have attached the code here because I had to fix some template code, adding/removing 'tyepename', as well as prevention of template parameter shadowing. As you already know, Microsoft's compiler is very 'flexible', allowing non-standard code to compile. Regards, Juan.

1 0

[filesystem] Please take care of #8706
by Antony Polukhin 10 Jul '13

10 Jul '13

Hi, There is a ticket https://svn.boost.org/trac/boost/ticket/8706 and patch in it that fixes compilation of Boost.Filesystem under Android NDK. Tested patch under latest NDK and it works well. Fix is required to start regression tests for droid platform. -- Best regards, Antony Polukhin

4 8

[function] Bind to std::function if supported?
by Andrew Ho 09 Jul '13

09 Jul '13

The boost::move library binds to std::move/T&&/etc. when the compiler supports such features, and only uses work-around mechanisms when the compiler lacks such support. Should we add similar support for boost::function? something like: #ifdef BOOST_FUNCTION_USE_STANDARD_LIBRARY_FUNCTION // alternative: #ifndef BOOST_NO_CXX11_HDR_FUNCTIONAL #include <functional> namespace boost { using ::std::function; } #else // whatever boost::function currently does #endif // ... something similar for boost::bind and std::bind I haven't looked at boost::atomic yet, but we could also consider similar bindings to std::atomic if the library doesn't already do so.

3 3

[shared_array] Why not in C++11 ?
by Sid Sacek 09 Jul '13

09 Jul '13

Does anyone know why 'boost::shared_array<>' was not made part of C++11, since pretty much all the other smart pointers were? -Sid

10 41

[context] SSE/AVX registers preservation
by Andrey Semashev 09 Jul '13

09 Jul '13

Hi, I've been looking at Boost.Context and wondering whether it preserves SSE/AVX state on context switches. From the code it doesn't look like the case - only jump_x86_64_ms_pe_masm.asm contains the code that saves some (not all) xmm registers and ymm registers are never saved. Is this intentional or the library simply doesn't support SSE/AVX? And why not use xsave/xrstor to consistently support all future extensions?

2 2

Re: [boost] Interest in a 'Boost.property' library?
by Joe Mucchiello 08 Jul '13

08 Jul '13

Personally, I always consider properties with getters/setters an anti-pattern for OOP languages like C++. Class interfaces should include only those methods that describe logically valid actions one might take on instances of the class. The idea of properties might sometimes be appropriate. But often times, programs will see a hammer and treat everything they see after it as nails. It becomes easy to add a few more getters and setters for "the rest" of the implementation details and you lose proper encapsulation. Usually when I find a class with lots of get/set methods I find a class with very little thought used when that class was designed.

4 7

[log] Setup Windows event log backends
by Renato Forti 08 Jul '13

08 Jul '13

Work well, on win 7/vc 11! Win 8/vc 11, don't work! mc is not detected! On Thu, Jul 4, 2013 at 11:38 PM, Renato Forti <re.tf(a)acm.org> wrote: > Hi, > I did, but don't work! I have mc, and I remove bin.v2. But boost build > don't find my mc :( > > - message-compiler : no > - compiler-supports-ssse3 : yes > - compiler-supports-avx2 : yes > - gcc visibility : no > - long double support : yes > > C:\boost_1_54_0>mc > Microsoft (R) Message Compiler Version 1.12.9200 Copyright (c) > Microsoft Corporation. All rights reserved. > > No cached! I am on Windows 8, and vc11! Thanks again! Hm, that's strange. Perhaps, a Win 8 thing? What does bin.v2/config.log say? _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

1 0

[unordered] a strange limitation for move emulation in Boost.Unordered
by Joaquin M Lopez Munoz 08 Jul '13

08 Jul '13

Here: http://www.boost.org/doc/html/unordered/compliance.html#unordered.complianc… it reads: "Non-copyable objects can be stored in the containers, but without support for rvalue references the container will not be movable." Why not? Container movement does not ever touch its elements, so I don't see the connection. Joaquín M López Muñoz Telefónica Digital

2 5

boost-1.54 needs a bugfix!
by Oliver Kowalke 08 Jul '13

08 Jul '13

unfortunately boost-1.54 needs a bugfix - because my request to merge boost.coroutine into release a required bugfix was not applied :( I'm wondering because the regression-tests are passed?! what to do? should I modify the fix in boost-release and archives of boost-1.54 are rebuild?

11 24

[fusion] Adapter for std::array
by Mateusz Loskot 07 Jul '13

07 Jul '13

Hi, I have prototyped Fusion adapter for std::array, as an attempt to clear the related feature request: https://svn.boost.org/trac/boost/ticket/8241 Here is the functional and testable code of the adaptor : https://github.com/mloskot/boost_fusion_std_array I will appreciate any critique and comments. Unfortunately, I have hit the apparently well-known problem. It is the Fusion begin/end ADL issues with C++0x range-based for and such, as discussed and reported here: http://lists.boost.org/Archives/boost/2010/12/174199.php https://svn.boost.org/trac/boost/ticket/4028 There has been no feedback to the ticket #8241, so I'm not sure what is the Fusion authors' view on std::array adoption. So, a couple of questions: Do the Fusion authors consider any cure for the ADL issues? If not, despite the inconvenience of use of qualified names, would it be still possible to accept std::array into Fusion? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

4 7

Interest in a 'Boost.property' library?
by Metodi Todorov 07 Jul '13

07 Jul '13

Is there any interest of "C# property" like library? struct vec2 { float get_x() const{...} float set_x() const{...} ... property_rw<float, vec2, &vec2::get_x, &vec2::set_x> x; vec2() : y(this) {} }; vec2 v; v.x = 15.0f; cout << v.x << endl; Example: http://sourceforge.net/projects/cproperty/?source=dlp Regards, Metodi Todorov

5 5

Benchmarking for performance?
by Arpan Sen 07 Jul '13

07 Jul '13

Hi Boost Dev, What sort of benchmarking does the community do for performance when moving from one revision to another? Kind of regression numbers for benchmark tests I would say for memory and time required. Does not have to be at an application level - even at a data structure level is a good start. Thanks a lot. Arpan

1 0

Historic of regression tests?
by Joaquin M Lopez Munoz 07 Jul '13

07 Jul '13

The regression tests at http://www.boost.org/development/tests/release/developer/summary.html are constantly updated (of course), but I seem to remember that the version manager used to backup a snapshot of this at each release. Am I right (I found nothing searching through boost.org)? Is there some sort of historic info on regression tests? Thank you, Joaquín M López Muñoz Telefónica Digital

2 1

[log] Setup Windows event log backends
by Renato Forti 06 Jul '13

06 Jul '13

Hi, I am trying setup a basic: <http://www.boost.org/doc/libs/1_54_0/libs/log/doc/html/log/detailed/sink_ba ckends.html#log.detailed.sink_backends.event_log> Windows event log, and I copy and past code from log documentation. My app link with: 1> main.cpp 1> Linking to lib file: boost_filesystem-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_system-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_log-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_thread-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_log_setup-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_date_time-vc110-mt-gd-1_54.lib 1> Linking to lib file: boost_chrono-vc110-mt-gd-1_54.lib But I have some link problems: 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::basic_si mple_event_log_backend<char>(void)" (__imp_??0?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAE@ XZ) referenced in function "class boost::shared_ptr<class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> > __cdecl boost::make_shared<class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> >(void)" (??$make_shared@V?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boos t@@@boost@@YA?AV?$shared_ptr@V?$basic_simple_event_log_backend@D@sinks@v2_mt _nt5@log@boost@@@0@XZ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::~basic_s imple_event_log_backend<char>(void)" (__imp_??1?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAE@ XZ) referenced in function "public: void * __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::`scalar deleting destructor'(unsigned int)" (??_G?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost@@QAEPAXI@Z ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::set_even t_type_mapper(class boost::log::v2_mt_nt5::aux::light_function<enum boost::log::v2_mt_nt5::sinks::event_log::event_type __cdecl(class boost::log::v2_mt_nt5::record_view const &)> const &)" (__imp_?set_event_type_mapper@?$basic_simple_event_log_backend@D@sinks@v2_mt _nt5@log@boost@@QAEXABV?$light_function@$$A6A?AW4event_type@event_log@sinks@ v2_mt_nt5@log@boost@@ABVrecord_view@456@@Z@aux@345@@Z) referenced in function "void __cdecl init_logging(void)" (?init_logging@@YAXXZ) 1>qt.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char>::consume( class boost::log::v2_mt_nt5::record_view const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (__imp_?consume@?$basic_simple_event_log_backend@D@sinks@v2_mt_nt5@log@boost @@QAEXABVrecord_view@345@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocat or@D@2@@std@@@Z) referenced in function "protected: void __thiscall boost::log::v2_mt_nt5::sinks::basic_formatting_sink_frontend<char>::feed_rec ord<class boost::log::v2_mt_nt5::aux::fake_mutex,class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> >(class boost::log::v2_mt_nt5::record_view const &,class boost::log::v2_mt_nt5::aux::fake_mutex &,class boost::log::v2_mt_nt5::sinks::basic_simple_event_log_backend<char> &)" (??$feed_record@Vfake_mutex@aux@v2_mt_nt5@log@boost@@V?$basic_simple_event_l og_backend@D@sinks@345@@?$basic_formatting_sink_frontend@D@sinks@v2_mt_nt5@l og@boost@@IAEXABVrecord_view@234@AAVfake_mutex@aux@234@AAV?$basic_simple_eve nt_log_backend@D@1234@@Z) What is wrong? Thanks

3 10

[log] Build fail : log (1.44.0) on vc 11 using cxxflags=-Zc:wchar_t-
by Renato Forti 05 Jul '13

05 Jul '13

Hi All, I need use cxxflags=-Zc:wchar_t-, because I will use boost with my QT project! I build boost like this (debug in this case): bjam toolset=msvc-11.0 variant=debug threading=multi link=shared cxxflags=-Zc:wchar_t- But log lib fail with this: call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-mul ti\formatter_parser.obj.rsp" ...failed compile-c-c++ ..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading -multi\formatter_parser.obj... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.dll for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.lib for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...skipped <p..\..\..\bin.v2\libs\log\build\msvc-11.0\debug\threading-multi>boos t_log_setup-vc110-mt-gd-1_54.pdb for lack of <p..\..\..\bin.v2\libs\log\build\ms vc-11.0\debug\threading-multi>boost_log-vc110-mt-gd-1_54.lib... ...failed updating 4 targets... ...skipped 6 targets... Anyone can helpeme? Thanks

3 6

gmp-5.1.2 / boost-1.54 / multiprecision lib
by Fred Schneider 05 Jul '13

05 Jul '13

Hello, I'm a bit of a newbie and I ran into some issues using gmp with boost. After building gmp-5.1.2, I tried to build a simple file: boostMathExample.cpp, based on the documentation (using the multiprecision library + referencing gmp): ////////////////////////////////////////// #include <boost/multiprecision/gmp.hpp> using namespace boost::multiprecision; int main(int argc, const char *argv[]) { mpz_int v = 1; // Do some arithmetic: for (unsigned int i = 1; i <= 1000; ++i) v *= i; std::cout << v << std::endl; } /////////////////////////////////////////////// I received the following missing symbol errors when trying to build: g++ -I ~/Dev/C++/gmp-5.1.2 -I ~/Dev/C++/boost boostMathExample.cpp -O2 -o boostMathExample Undefined symbols: "_main", referenced from: start in crt1.10.6.o "___gmpz_init", referenced from: __static_initialization_and_destruction_0(int, int)in cccOFSnR.o __static_initialization_and_destruction_0(int, int)in cccOFSnR.o "___gmpz_clear", referenced from: ___tcf_1 in cccOFSnR.o __static_initialization_and_destruction_0(int, int)in cccOFSnR.o "___gmpz_set_si", referenced from: __static_initialization_and_destruction_0(int, int)in cccOFSnR.o ld: symbol(s) not found collect2: ld returned 1 exit status ======================================== I'm running the following version of g++: i686-apple-darwin10-g++-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5666) (dot 3) I configured gmp, version 5.1.2 with the following flags: ./configure --enable-cxx CXX=g++ CXXFLAGS=-O2 CC=g++ CFLAGS="-g -O2" and then ran "make" and "make check". Any insight would be appreciated. Thanks, Fred

3 3

[algorithm][minmax_element] implementation question
by Michael Marcin 04 Jul '13

04 Jul '13

I was looking at minmax_elemement to try and understand the algorithm. I noticed that the boost implementation looks significantly more complicated than the clang libc++ implementation. Mainly due to the potential_min_result variable that exists in the boost version. Is there a reason for this discrepancy? Is there a bug in the clang implementation? http://llvm.org/svn/llvm-project/libcxx/trunk/include/algorithm http://www.boost.org/doc/libs/1_54_0/boost/algorithm/minmax_element.hpp

3 2

Re: [boost] [utility][thread] result_of - erroneous result type from a C++11 lambda
by Klaim - Joël Lamotte 04 Jul '13

04 Jul '13

On Tue, Apr 2, 2013 at 7:16 PM, Vicente J. Botet Escriba < vicente.botet(a)wanadoo.fr> wrote: > I've started to use C++11 lambda functions with Boost.Thread. > > The following works with clang-3.2 > > boost::future<int> f1 = boost::async( []() -> int {return 123;} ); > > > But it fails with gcc-4.6.2, 4.7.2 and 4.8.0 > > ../example/lambda_future.cpp:**25:91: erreur: conversion from > ‘boost::future<void>’ to non-scalar type ‘boost::future<int>’ requested > boost::future<int> f1 = boost::async( []() -> int {return 123;} ); > > The current implementation of boost::async uses boost::result_of to get > the result type of the callable parameter. > > Is this a know bug on boost::result_of or gcc compiler? > I'm seeing exactly the same behaviour in *VS2012 Update 2*. I'm using Boost 1.54.0 beta *r84748* To be more precise: 1) I first was just using boost::future and tried to use the new .then(), here is a full repro: #include <boost/thread/future.hpp> auto ft = boost::async( []{ return 42; } ).then( []( boost::future<int> r ){ return 666; } ); This fails because boost::async() returned a future<void> instead of a future<int>. I suspect the then() call to have the same problem. I can provide the full error log but I think it's not that useful. 2) Just to be sure I tried this full test: #include <boost/thread/future.hpp> int main() { auto ft = boost::async( []{ return 42; } ); // SUCCEED: static_assert( std::is_same< decltype(ft), boost::future<void> >::value, "WTF???" ); // FAILS: static_assert( std::is_same< decltype(ft), boost::future<int> >::value, "Not the expected type!" ); } Both asserts confirm that I don't get what I want. 3) I remembered that there were some issues from usage of boost::result_of in Boost.Log, so to clarify the situation I setup the following full test: #include <boost/utility/result_of.hpp> #include <type_traits> int top() { return 42; } struct K { int operator()(){ return 42; } typedef int value_type; }; auto F = []{ return 42; }; int main() { // A: ALL SUCCEED static_assert( std::is_same< decltype(K()()), int >::value, "Not the expected type!" ); static_assert( std::is_same< decltype(top()), int >::value, "Not the expected type!" ); static_assert( std::is_same< decltype(F()), int >::value, "Not the expected type!" ); // B: ALL SUCCEED static_assert( std::is_same< std::result_of<K()>::type, int >::value, "Not the expected type!" ); static_assert( std::is_same< std::result_of<decltype(top)>::type, int >::value, "Not the expected type!" ); static_assert( std::is_same< std::result_of<decltype(F)()>::type, int >::value, "Not the expected type!" ); // C: ALL SUCCEED std::result_of<K()>::type a = K()(); std::result_of<decltype(top)>::type b = top(); std::result_of<decltype(F)()>::type c = F(); // D: ALL FAILS static_assert( std::is_same< boost::result_of<K()>::type, int >::value, "Not the expected type!" ); static_assert( std::is_same< boost::result_of<decltype(top)>::type, int >::value, "Not the expected type!" ); static_assert( std::is_same< boost::result_of<decltype(F)()>::type, int >::value, "Not the expected type!" ); // E: ALL FAILS boost::result_of<K()>::type d = K()(); // error C2182: 'd' : illegal use of type 'void' boost::result_of<decltype(top)>::type e = top(); // error C2182: 'e' : illegal use of type 'void' boost::result_of<decltype(F)()>::type f = F(); // error C2182: 'f' : illegal use of type 'void' } This shows clearly that: 1. boost::result_of don't behave like std::result_of on this platform (and from previous discussions, on other platforms too). 2. both std::result_of and decltype() provide the result I expect from reading documentations about these. So far I'm assuming that the problem really is from boost::result_of, but I might be wrong because the differences with std::result_of are not clear to me. ---- Unfortunately this makes future.then() unusable if we expect return types. I don't know if it impacts other libraries (I suspect Boost.Log). Should I report a bug or is it known, already fixed or a misuse? Joel Lamotte

5 12

[result_of] Documentation update for ticket 7753
by Nathan Crookston 03 Jul '13

03 Jul '13

Hi Daniel & all, I'm updating the patch for ticket 7753 ( https://svn.boost.org/trac/boost/ticket/7753) I've made the requested changes to the patch, but I had a question on how to best explain which macro to define if, for example, you want result_of to work with C++11 lambdas. In the past, users with a pre-N3276 decltype have been advised to just #define BOOST_RESULT_OF_USE_DECLTYPE, with the explanation that "it's probably just going to work." While that advice is true, there are cases where this doesn't work; hence the addition of BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK. To explain why you'd define the FALLBACK macro over the USE_DECLTYPE macro, I'm thinking of including a paragraph like the following. "The question naturally arises on why have both BOOST_RESULT_OF_USE_DECLTYPE and BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK. In many situations, BOOST_RESULT_OF_USE_DECLTYPE will work well, even with pre-N3276 decltype. However, there are cases where a post-N3276 decltype is required to correctly deduce the return type of a functor. If a translation unit includes a functor whose return type is only deducible with TR1 or a post-N3276 decltype, using result_of with, e.g. a C++11 lambda function, will fail without BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK. If the macro BOOST_NO_CXX11_DECLTYPE_N3276 is defined and BOOST_NO_CXX11_DECLTYPE is not defined when including result_of.hpp, defining BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK is the safest option that will allow you to deduce C++11 lambda return types." My question is, am I over explaining it? Of course, I'd rather have BOOST_RESULT_OF_USE_TR1_WITH_DECLTYPE_FALLBACK defined automatically for compilers like VC10, g++4.5, etc., and include text like the following: "If you rely on the result of calling a nullary functor to be void, regardless of the actual return type, or if your code is not written to handle cases other than BOOST_RESULT_OF_USE_TR1 and BOOST_RESULT_OF_USE_DECLTYPE, you may wish to explicitly define one of those symbols prior to including result_of." Either way, comments welcome. Thanks, Nate

3 4

Want to contribute, need advice.
by Manmohit Rekhi 03 Jul '13

03 Jul '13

Hello, Am Manmohit Rekhi, a 2nd year computer engineering student at Nirma university, India. I have some programming experience in c and c++. Am interested in contributing to Boost, and would like to ask a few questions, to help me get started. I would be really grateful is, i could get the following questions answered. 1) Do i need to be familiar with the code of the standard c++ libraries, and if so, where do i start? 2) What other per-requisites are there? 3) Where do i start reading the boost libraries(i mean which file to read first)? Thanking You, Manmohit Rekhi

2 1

[Serialization] Constructor for polymorphic archives
by Bjorn Reese 03 Jul '13

03 Jul '13

I have a set of my own Boost.Serialization archives (e.g. [1]) that I wish to write polymorphic variants of. I have tried to follow the blueprint from polymorphic_text_iarchive, which inherits from polymorphic_iarchive_route. The problem is that the constructor of my archives takes iterators (begin and end) as arguments, but the polymorphic_iarchive_route constructor expects a std::stream argument. Is there any workaround for this? [1] http://sourceforge.net/p/protoc/code/ci/master/tree/include/protoc/transenc…

3 4

[Operators] Update, const-correctness and operator chaining
by Andrew Ho 02 Jul '13

02 Jul '13

Hi, I was doing some testing with Daniel Frey/Marc Glisse's proposed 4- overload set for binary operators. For reference, here's the overload set applied to commutative addition: friend T operator +( const T& lhs, const T& rhs) { T nrv(lhs); nrv += rhs; return nrv; } friend T operator +(T&& lhs, const T& rhs) { return std::move(lhs += rhs); } friend T operator +(const T& lhs, T&& rhs) { T nrv(lhs); nrv += boost::move(rhs); return nrv; } friend T operator +(T&& lhs, T&& rhs) { return boost::move(lhs += boost::move(rhs)); } This allows this to be done: val1 + val2 = val3; changing the return type to const T would allow the compiler to catch this, but now doing val1 + val2 + val3 must always use copy semantics instead of move semantics. I can't think of a way which would fix this issue without breaking the use of move semantics. How should we proceed with this? It's obviously bad usage, but the compiler should be able to catch this since it's easy to mistype + as =. Interestingly enough, doing testing with std::string shows the same "problem": std::string str1("hello"), str2(" "), str3("world"); str1 + str2 = str3; I tested this issue with std::string and found it in vs2012, gcc 4.3.2, and mingw/gcc 4.8.0. I don't have access to a compiler which pre-dates C++0x/C++11 so I don't know if this issue has always been present. Compiling with gcc 4.8.0 with - std=c++03 still has the issue.

3 3

Any interest in bitstream class?
by Paul Long 02 Jul '13

02 Jul '13

Same semantics as, e.g., stringstream, but it operates on binary data. I already have the analogues to istringstream/stringbuf (you can take a look at ibitstream/bitbuf at https://github.com/dplong/bstream) There are some interesting features, but I won't go into them here. If there is interest, I would implement obitstream and bitstream and possibly support Boost::dynamic_bitset. The rationale is _succinct_ expression of predictive parsing of binary data. I've used ibitstream in production code for decoding RTP headers and frames of various video encodings. Below is a simple function that decodes an RTP header using ibitstream; I also have a GitHub repo that contains more complex code for high-level parsing of H.264 frames at https://github.com/dplong/rtspudph264 struct RtpHeader { bool padding, marker; bitset<7> payloadType; WORD sequenceNumber; DWORD timestamp, ssrcIdentifier; vector<DWORD> csrcIdentifier; struct { bool present; WORD identifier; vector<BYTE> contents; } extension; }; bool ParseRtpHeader(const BYTE *buffer, RtpHeader &rtp) { ibitstream bin(buffer); static const bitset<2> version(0x2); bitset<4> csrcCount; WORD extensionLength; bin >> version >> rtp.padding >> rtp.extension.present >> csrcCount >> rtp.marker >> rtp.payloadType >> rtp.sequenceNumber >> rtp.timestamp >> rtp.ssrcIdentifier >> setrepeat(csrcCount.to_ulong()) >> rtp.csrcIdentifier; if (rtp.extension.present) { bin >> rtp.extension.identifier >> extensionLength >> setrepeat(extensionLength * sizeof(DWORD)) >> rtp.extension.contents; } return bin.good(); }

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Static initialization of boost shared objects question
by Juan Carlos Franzoy 02 Jul '13

02 Jul '13

Hello. Thanks for reading my question. I fell into a deadlock in static initialization of boost shared objects. The deadlock occurs in a reentrant call to a function which contains a definition of a static variable. Apparenlty gcc protects the initialization of such variables with a condition variable. Looking at the c++ code nothing at all make anybody suspect about reentrancy. My "interpretation of the fact" may be titled 'something in gcc, ld, ld.so, c++language made the call to be reentrant' - There is a function boost::system::generic_category() that has a static variable V - V type is boost::system::annonymous-namespace::generic_error_category - boost::system::annonymous-namespace::generic_error_category is subclass of boost::system::error_category. - boost::system::annonymous-namespace::generic_error_category has no declared/defined constructor as well as all its superclasses - The compilation process generate the constructor boost::system::error_category::error_category() as a weak symbol inside every shared object that uses it. - There is a static variable boost::system::posix_category in one of the shared objects that is initialized calling boost::system::generic_category(). - when the static initialization of a shared object boost::system::posix_category get initialized - which calls boost::system::generic_category() - Inside boost::system::generic_category() starts the initialization of V which calls boost::system::error_category::error_category() - It may happend that the runtime calls an instance of boost::system::error_category::error_category() that resides in a shared object that is still not loaded - So that .so get loaded and it is called its own static initialization - which can call boost::system::generic_category() - BOOM I would love if you can confirm of refute my humble "interpretation". Details follows ------------------- boost version: 1-52-0 Operating system: uname -a SunOS bcpp-solaris10 5.10 Generic_147441-25 i86pc i386 i86pc $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/export/home/local/gcc-4.6.2/libexec/gcc/i386-pc-solaris2.10/4.6.2/lto-wrapper Target: i386-pc-solaris2.10 Configured with: ../src/gcc-4.6.2/configure --prefix=/export/home/local/gcc-4.6.2 --with-gmp=/export/home/local/gcc-4.6.2/gmp-4.3.2 --with-mpfr=/export/home/local/gcc-4.6.2/mpfr-3.0.0 --with-mpc=/export/home/local/gcc-4.6.2/mpc-0.8.2 --with-libelf=/export/home/local/gcc-4.6.2/libelf-0.8.12 --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --enable-languages=c,c++ --with-as=/usr/local/bin/as --with-gnu-as --with-ld=/usr/ccs/bin/ld --without-gnu-ld --enable-plugin --enable-multilib --enable-version-specific-runtime-libs --enable-bootstrap --enable-ssp --enable-libssp --with-included-gettext --enable-lto --host=i386-pc-solaris2.10 --build=i386-pc-solaris2.10 Thread model: posix gcc version 4.6.2 (GCC) Callstack backtrace (lines begining with = are my comments): = = deadlock here: the threads is waiting itself = #0 0xfd459019 in __lwp_park () from /lib/libc.so.1 #1 0xfd45365e in cond_sleep_queue () from /lib/libc.so.1 #2 0xfd453817 in cond_wait_queue () from /lib/libc.so.1 #3 0xfd453b94 in cond_wait_common () from /lib/libc.so.1 #4 0xfd453d02 in _cond_wait () from /lib/libc.so.1 #5 0xfd453d2d in cond_wait () from /lib/libc.so.1 #6 0xfd453d66 in pthread_cond_wait () from /lib/libc.so.1 #7 0xfd632898 in __gthread_cond_wait (g=0xfd822ea8) at ...build-gcc/out/i386-pc-solaris2.10/libstdc++-v3/include/i386-pc-solaris2.10/bits/gthr-default.h:846 #8 __gthread_cond_wait_recursive (g=0xfd822ea8) at ...work/build-gcc/out/i386-pc-solaris2.10/libstdc++-v3/include/i386-pc-solaris2.10/bits/gthr-default.h:860 #9 __gnu_cxx::__cond::wait_recursive (g=0xfd822ea8) at ...build-gcc/out/i386-pc-solaris2.10/libstdc++-v3/include/ext/concurrence.h:377 #10 __cxa_guard_acquire (g=0xfd822ea8) at .../src/gcc-4.6.2/libstdc++-v3/libsupc++/guard.cc:289 = = Reentrant call to boost::system::generic_category() = #11 0xfd812313 in boost::system::generic_category () at libs/system/src/error_code.cpp:425 #12 0xfe85cd38 in __static_initialization_and_destruction_0(__initialize_p=1, __priority=65535) at ./boost/system/error_code.hpp:214 #13 0xfe85d05f in _GLOBAL__sub_I_instantiate_re2c_lexer_str.cpp () at libs/wave/src/instantiate_re2c_lexer_str.cpp:56 = = static initization of boost.wave library = #14 0xfe8868fd in __do_global_ctors_aux () from ...boost/lib/libboost_wave-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #15 0xfe88692a in _init () from ...boost/lib/libboost_wave-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #16 0xfefce37e in call_init () from /usr/lib/ld.so.1 #17 0xfefce1cf in is_dep_init () from /usr/lib/ld.so.1 #18 0xfefdaa4b in elf_bndr () from /usr/lib/ld.so.1 #19 0xfefc2ab4 in elf_rtbndr () from /usr/lib/ld.so.1 #20 0xfee60688 in ?? () #21 0xfee0c8f6 in boost::exception_detail::get_static_exception_object<boost::exception_detail::bad_alloc_>() at ./boost/exception/detail/exception_ptr.hpp:119 #22 0xfee0c0d2 in __static_initialization_and_destruction_0(__initialize_p=1, __priority=65535) at ./boost/exception/detail/exception_ptr.hpp:138 #23 0xfee0c271 in _GLOBAL__sub_I_future.cpp () at libs/thread/src/future.cpp:60 = = static initization of boost.thread library = #24 0xfee0d98d in __do_global_ctors_aux () from ...boost/lib/libboost_thread-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #25 0xfee0d9ba in _init () from ...boost/lib/libboost_thread-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #26 0xfefce37e in call_init () from /usr/lib/ld.so.1 #27 0xfefce1cf in is_dep_init () from /usr/lib/ld.so.1 #28 0xfefdaa4b in elf_bndr () from /usr/lib/ld.so.1 #29 0xfefc2ab4 in elf_rtbndr () from /usr/lib/ld.so.1 #30 0xfdce0688 in ?? () = = First calll to boost::system::generic_category() = #31 0xfd81232a in boost::system::generic_category () at libs/system/src/error_code.cpp:425 #32 0xfd812386 in __static_initialization_and_destruction_0(__initialize_p=1, __priority=65535) at ./boost/system/error_code.hpp:214 #33 0xfd8123ed in _GLOBAL__sub_I_error_code.cpp () at libs/system/src/error_code.cpp:430 = = static initialization of boost.system = #34 0xfd8126ed in __do_global_ctors_aux () from ...boost/lib/libboost_system-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #35 0xfd81271a in _init () from ...boost/lib/libboost_system-gcc46-mt-d-32-SOLARIS-X86-1_52.so.1.52.0 #36 0xfefce37e in call_init () from /usr/lib/ld.so.1 #37 0xfefcd7d5 in setup () from /usr/lib/ld.so.1 #38 0xfefdba3e in _setup () from /usr/lib/ld.so.1 #39 0xfefc299c in _rt_boot () from /usr/lib/ld.so.1 #40 0x08047540 in ?? () #41 0x08047670 in ?? () More thanks for reading all.

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zlib not building (fedora x86_64)
by Neal Becker 02 Jul '13

02 Jul '13

I noticed zlib are not being built. I don't know why. rpm -qa zlib* zlib-1.2.7-9.fc18.i686 zlib-1.2.7-9.fc18.x86_64 zlib-devel-1.2.7-9.fc18.x86_64 bjam cxxflags=-march=native -sHAVE_ICU=1 -sEXPAT_INCLUDE=/usr - sEXPAT_LIBPATH=/usr/lib64 --layout=tagged threading=single,multi link=shared stage warning: No toolsets are configured. warning: Configuring default toolset "gcc". warning: If the default is wrong, your build may not work correctly. warning: Use the "toolset=xxxxx" option to override our guess. warning: For more configuration options, please consult warning: http://boost.org/boost-build2/doc/html/bbv2/advanced/configuration.html Performing configuration checks - 32-bit : no - 64-bit : yes - arm : no - mips1 : no - power : no - sparc : no - x86 : yes error: No best alternative for libs/coroutine/build/allocator_sources next alternative: required properties: <link>static <target-os>windows <threading>multi not matched next alternative: required properties: <link>static <segmented-stacks>on <threading>multi not matched next alternative: required properties: <link>static <threading>multi not matched - has_icu builds : yes warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam - zlib : no - iconv (libc) : yes - icu : yes - compiler-supports-ssse3 : yes - compiler-supports-avx2 : yes - gcc visibility : yes - long double support : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. error: No best alternative for libs/coroutine/build/allocator_sources next alternative: required properties: <link>static <target-os>windows <threading>multi not matched next alternative: required properties: <link>static <segmented-stacks>on <threading>multi not matched next alternative: required properties: <link>static <threading>multi not matched - zlib : no (cached) Component configuration: - atomic : building - chrono : building - context : building - coroutine : building - date_time : building - exception : building - filesystem : building - graph : building - graph_parallel : building - iostreams : building - locale : building - log : building - math : building - mpi : building - program_options : building - python : building - random : building - regex : building - serialization : building - signals : building - system : building - test : building - thread : building - timer : building - wave : building

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boost 1.54.0 support for VS2013
by Charles_J_Wilson＠Dell.com 01 Jul '13

01 Jul '13

Has visualc.hpp been updated to support VC++12? (this was released in Visual Studio 2013 preview). I get the following issue with 1.54.0 beta built with VC++11 when compiling using VC++12: Error 1 error C2039: 'assert_not_arg' : is not a member of 'boost::mpl' (..\..\..\Logging\source\Core.cpp) C:\Users\Charles_J_Wilson\Documents\Projects\external\open_source\boost\1.54.0\boost_1_54_0\boost\iterator\detail\facade_iterator_category.hpp 166 Which is: # if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) BOOST_MPL_ASSERT_NOT((is_iterator_category<Traversal>)); # endif The beta doesn't recognize the compiler version and suggests running the config tests. Where are the instructions for that? Charles Wilson Principal Software Development Engineer Dell | Enterprise Solutions Group

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