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testers blocked after changeset 85924 in trunk.
by Vicente J. Botet Escriba 01 Oct '13

01 Oct '13

Hi, the last change set that has been taken in account in trunk regression test is 85924. I'm expecting a lot of testers to cycle. Note that release regressing test are not blocked. Could someone explain what is happening? Best, Vicente

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Review request: Require compiler support for partial template specialization.
by Stephen Kelly 01 Oct '13

01 Oct '13

Hi there, Following from http://thread.gmane.org/gmane.comp.lib.boost.devel/243923/focus=243924 I am posting a more focused and specific request to review a patch to bump compiler requirements to require support for partial template specialization. This allows the removal of a lot of workaround code: src/boost-trunk{master}$ ../kf5/remove_def.py BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION src/boost-trunk{master}$ git diff --shortstat 192 files changed, 4798 deletions(-) Obviously I would not commit all of that as a single patch. Any comments? Thanks, Steve.

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Do/can we have a C++11 variadic integer list?
by Daryle Walker 01 Oct '13

01 Oct '13

I'm talking about this: template < std::size_t ...N > struct indices_too { using next = indices_too<N..., sizeof...(N)>; }; template < std::size_t N > struct make_indices_too { using type = typename make_indices_too<N - 1u>::type::next; }; template < > struct make_indices_too<0u> { using type = indices_too<>; }; I've written things like this 4 times for my prototype Boost classes, and I want it in Boost already so I can just reference that version. Something like it will come in C++14, but we could provide it here for C++11 users? Do we already have one? Here's how to use one: template < typename Function, typename T, class Tuple, std::size_t ...I > void apply_x_and_exploded_tuple_impl( Function &&f, T &&x, Tuple &&t, indices_too<I...> ) { using std::forward; forward<Function>( f )( forward<T>(x), forward<typename std::tuple_element<I, typename std::remove_reference<Tuple>::type>::type>(std::get<I>( t ))... ); } template < typename Function, typename T, class Tuple > void apply_x_and_exploded_tuple( Function &&f, T &&x, Tuple &&t ) { using std::forward; apply_x_and_exploded_tuple_impl( forward<Function>(f), forward<T>(x), forward<Tuple>(t), typename make_indices_too<std::tuple_size<typename std::remove_reference<Tuple>::type>::value>::type{} ); } Daryle W.

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orphaned tickets
by Joel Falcou 01 Oct '13

01 Oct '13

What's the protocol to handle lingering tickets of un maintained components. I wish #9169 and #9170 could be merged to trunk soonish. I cna do it myself but i dont want to breach any protocol. Regards

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REQ: Looking for access to a Haswell machine to test Boost memory transactions code
by Niall Douglas 30 Sep '13

30 Sep '13

Dear Boost Devs, Last night I may have implemented some Boost macro based support for simple memory transactions. Basically one does this: STLLockable lockable; ... BOOST_BEGIN_MEMORY_TRANSACTION(lockable) { // Transaction code } BOOST_END_MEMORY_TRANSACTION(lockable) This can turn into __transaction_relaxed, or Intel TSX falling back onto a spin lock. It's very simple, but it ought to work and with very significant performance improvements on TSX capable hardware. The problem is that I don't have access to an Intel Haswell CPU to test the code upon. I think its design is correct through introspection, but if a kind Boost dev could lend me access to their Haswell machine via SSH - or even just offer to debug some binaries for me, I would be very grateful. Thanks, Niall -- Currently unemployed and looking for work. Work Portfolio: http://careers.stackoverflow.com/nialldouglas/

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[release][interprocess] regression in Windows
by Joaquin M Lopez Munoz 30 Sep '13

30 Sep '13

As indicated by the regression testers, see for instance: http://tinyurl.com/qabv7dm This is affecting also Boost.Flyweight, which uses <boost/interprocess/detail/intermodule_singleton.hpp> for its intermodule_holder component. Thank you, Joaquín M López Muñoz Telefónica Digital

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Boost and clang under Windows
by Edward Diener 30 Sep '13

30 Sep '13

First off I am not of course proposing any changes to the upcoming release build of Boost 1.55 for clang under Windows. It turns out that clang under Windows, possibly to support the ability to use Windows header file, becomes another compiler which defines _MSC_VER. I believe the Intel compiler also does this but there may be some others. However clang is a much more strictly conforming to the C++ standard compiler than VC++ and does not have VC++'s quirks. This presents a problem in Boost. The Boost header files have numerous places where testing the macro _MSC_VER produces slightly different behavior based on the fact that the code is being used by VC++ or a compiler with the same behavior as VC++. But clang does not have the same behavior as VC++ despite defining _MSC_VER. Can I go ahead and change some of these situations as necessary to get clang under Windows to work properly with Boost code ? The usual change will be to test not only _MSC_VER but also that __clang__ is not defined for keeping the current implementation which assumes a VC++ compatible compiler with VC++ behavior. I am willing to make those changes in 'trunk' and keep an eye out for any significant failures in unit tests for our current regression tests. I have already made a slight change to Boost PP config.hpp on 'trunk' so that clang for Windows will pass the preprocessor tests. I am willing to work on other changes but I do not want to go ahead and do so if the maintainers of other libraries see any reasons for me not making the changes on 'trunk'. Of course I will test any changes I make locally to make sure they do not affect any other _MSC_VER defined compilers as well as with VC++. But the changes themselves should be fairly simple, just adding a check that __clang__ is not defined as part of the VC++ type behavior. Obviously something like the many tests for _MSC_VER in order to specify #pragma once will not change but some other situations will to exclude clang from the _MSC_VER functionality.

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[clang][Windows] Volunteer for a Boost regression test runner for Clang on Windows
by Beman Dawes 30 Sep '13

30 Sep '13

Chandler Carruth has asked for a volunteer to start running boost regression tests for the Clang on Windows project. For more about this project, see http://blog.llvm.org/2013/09/a-path-forward-for-llvm-toolchain-on.html. Chandler cornered me at the C++ committee meeting last week, and emphasized how much they would like to see boost tests passing using Clang in a Visual Studio environment. This would be a big plus for boost developers and users in the Windows environment IMO, so I hope we can help them out. This project is at an early stage, and many boost tests currently fail, so there is a lot of work to be done. --Beman

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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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Program Options library and Unicode compliance
by munsingh 30 Sep '13

30 Sep '13

I noticed that the class option_description does not work with wstring, instead works with string. Does anyone has any idea why is it so? Regards, Manish -- May the force be with you

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