- Boost - lists.preview.boost.org

[interval] rounded_arith_opp doesn't work in Release configuration under msvc 14
by Peter Azmanov 25 Feb '16

25 Feb '16

Hello, Interval calculations with rounded_arith_opp in Release configuration under msvc 14 result in zero-size intervals. For example consider following: #include <iostream> #include <boost/numeric/interval.hpp> int main(int argc, char * argv[]) { unsigned int ctrl = _control87(0, 0); _control87(_EM_INEXACT | _RC_UP, _MCW_EM | _MCW_RC); using namespace boost::numeric::interval_lib; typedef typename unprotect< boost::numeric::interval<double> >::type interval_t; interval_t test = interval_t(1.) / interval_t(3.); std::cout << "test.lower() != test.upper(): " << std::boolalpha << (test.lower() != test.upper()) << std::endl; return 0; } This test unexpectedly prints: test.lower() != test.upper(): false Tested on x64 platform with /fp:strict and /fp:precise under MS Visual Studio Community 2015 Version 14.0.24720.00 Update 1, Boost 1.60. I've already reported this to https://svn.boost.org/trac/boost/ticket/12018 There you can find some details of what I think is going wrong and proposed workaround patch. I didn't create pull request because I'm not sure if my patch is a correct workaround. Maybe someone will propose more appropriate solution. Best regards, Peter Azmanov.

1 0

Re: [boost] Removal of boost::basic_string_ref (in favor of basic_string_view)
by Bjorn Reese 25 Feb '16

25 Feb '16

On 02/17/2016 08:52 PM, Marshall Clow wrote: > I have just removed boost::basic_string_ref from the develop branch, and > updated the specializations to use basic_string_view. I am against this decision. I am using basic_string_ref<> quite heavily in several projects that have work with Boost 1.55 and newer.

4 4

[spirit] develop test problems
by Robert Ramey 24 Feb '16

24 Feb '16

For some time now, the serialization library fails to compile on the develop branch. The test matrix for some platforms indicates syntax error in some spirit file. On other platforms, the library build is reported to "succeed" but the it still seems that library build fails. This error also shows up in the spirit library tests. see http://www.boost.org/development/tests/develop/developer/output/teeks99-09e… Is there any time frame for addressing this? It's currently creating test failures on library which depend directly or indirectly on spirit/classic. Robert Ramey

3 3

[geometry][pool][ptr_container][typeof][auto_index][quickbook] Merge to master planned for release?
by Rene Rivera 24 Feb '16

24 Feb '16

There are some changes I did to the cited libraries and tools to deal with some release build infrastructure. I need to know if the maintainers of them are going to merge their respective develop branches to master? I need to know so that I can move forward as quickly as possible to generating CI release packages for the upcoming 1.61 release. Note: If I don't hear soon I might need to do some merging myself on your libraries/tools and end up messing something up ;-) So I would prefer if the maintainers do it. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

4 9

Regression impacting chrono
by Raffi Enficiaud 23 Feb '16

23 Feb '16

Dear all, There is a regression between 180bee and 372c53 on VS, and apparently boost.chrono (and indirectly boost.test...) is impacted: See http://www.boost.org/development/tests/develop/developer/output/teeks99-08e… trace below: ================= cl /Zm800 -nologo @"D:\t08\run\results\boost\bin.v2\libs\chrono\build\msvc-12.0\dbg\adrs-mdl-64\lnk-sttc\thrd-mlt\process_cpu_clocks.obj.rsp" process_cpu_clocks.cpp D:\t08\run\boost_root\boost/system/error_code.hpp(431) : error C2872: 'detail' : ambiguous symbol could be 'boost::detail' or 'boost::operators_impl::detail' ================= Between those 2 revisions, there were updates on - context - dll - system - utility - winapi Thanks, Raffi

2 2

[utility] Re: Massive test failures due to ambiguous namespace
by Rene Rivera 23 Feb '16

23 Feb '16

On Tue, Feb 23, 2016 at 1:31 PM, Markus Trippelsdorf <markus(a)trippelsdorf.de > wrote: > http://www.boost.org/development/tests/develop/developer/summary.html > show many "fails" due to: > > In file included from ../libs/chrono/src/process_cpu_clocks.cpp:17: > In file included from > ../boost/chrono/detail/inlined/process_cpu_clocks.hpp:19: > In file included from ../boost/chrono/process_cpu_clocks.hpp:22: > In file included from ../boost/chrono/detail/system.hpp:12: > ../boost/system/error_code.hpp:431:15: error: 'detail' is not a class, > namespace, or scoped enumeration > { return *detail::throws(); } > ^ > ../boost/system/error_code.hpp:431:15: error: reference to 'detail' is > ambiguous > { return *detail::throws(); } > ^ > ../boost/system/error_code.hpp:421:13: note: candidate found by name > lookup is 'boost::detail' > namespace detail { inline system::error_code * throws() { return 0; } } > ^ > ../boost/operators.hpp:658:11: note: candidate found by name lookup is > 'boost::operators_impl::detail' > namespace detail > ^ > 2 errors generated. > Also.. This is affecting general building of release packages. First time it showed up was with this superproject update < https://travis-ci.org/boostorg/boost/jobs/111041426>. Please fix ASAP! -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 2

Massive test failures due to ambiguous namespace
by Markus Trippelsdorf 23 Feb '16

23 Feb '16

http://www.boost.org/development/tests/develop/developer/summary.html show many "fails" due to: In file included from ../libs/chrono/src/process_cpu_clocks.cpp:17: In file included from ../boost/chrono/detail/inlined/process_cpu_clocks.hpp:19: In file included from ../boost/chrono/process_cpu_clocks.hpp:22: In file included from ../boost/chrono/detail/system.hpp:12: ../boost/system/error_code.hpp:431:15: error: 'detail' is not a class, namespace, or scoped enumeration { return *detail::throws(); } ^ ../boost/system/error_code.hpp:431:15: error: reference to 'detail' is ambiguous { return *detail::throws(); } ^ ../boost/system/error_code.hpp:421:13: note: candidate found by name lookup is 'boost::detail' namespace detail { inline system::error_code * throws() { return 0; } } ^ ../boost/operators.hpp:658:11: note: candidate found by name lookup is 'boost::operators_impl::detail' namespace detail ^ 2 errors generated. -- Markus

1 0

boost::container::set insert range bug
by Han Wang 23 Feb '16

23 Feb '16

Hi, Let's say we have some simple code here. boost::container::set<int> s; boost::container::set<int> const sp; s.insert(boost::begin(sp), boost::end(sp)); This insert call will cause "ambiguous call to overloaded function". Best regards, Han

2 1

GSoC Project Proposal - Boost Document Library Extensions
by Anurag Ghosh 23 Feb '16

23 Feb '16

Hello everyone! I wished to propose continue working on the Boost Document Library as a part of the Google Summer of Code 2016, and would like to work on the following things this summer on the library which was started last summer - 1. Integrating Basic Chart Support. 2. Writing comparators for the cells. (Cells are heterogeneous in nature, similar to Boost.Variant) 3. Making cell class have the behavior of a reference to the document's cell. 4. Basic formatting options for cell contents. Kindly make appropriate suggestions to my proposal. The aim of the proposal is to make it a Boost-Ready library. I would remind everyone that the library in its current state has basic spreadsheet functionality like opening, closing and exporting documents, sheet operations and cell,row,column (iterators) operations for Linux and Windows through wrappers over LibreOffice and Microsoft Office API's. ( https://github.com/BoostGSoC15/boost-document) I have been inactive for sometime, but I hope to improve test coverage before March and fix some other issues. Thanks Anurag Ghosh researchweb.iiit.ac.in/~anurag.ghosh

1 0

[Core] BOOST_TRY/BOOST_CATCH
by Chris Glover 22 Feb '16

22 Feb '16

Hi, I ran into a problem when trying to use BOOST_TRY/BOOST_CATCH to add no-exception support to property tree. Here's an example of the original code; try { write_ini(stream, pt, flags); } catch (ini_parser_error &e) { BOOST_PROPERTY_TREE_THROW(ini_parser_error( e.message(), filename, e.line())); } I converted this code to use the macros from core/no_exception_support.hpp *BOOST_TRY *{ write_ini(stream, pt, flags); } *BOOST_CATCH *(ini_parser_error &e) { BOOST_PROPERTY_TREE_THROW(ini_parser_error( e.message(), filename, e.line())); } *BOOST_CATCH_END* The issue is that now the exception, ini_parser_error& e, is not defined when I compile with exceptions off. I solved this by adding a local instance of ini_parser_error above the try block *ini_parser_error e("", "", 0);* BOOST_TRY { write_ini(stream, pt, flags); } BOOST_CATCH (ini_parser_error &e) { BOOST_PROPERTY_TREE_THROW(ini_parser_error( e.message(), filename, e.line())); } BOOST_CATCH_END This is a little gross, but it's not too bad and I was expecting the variable to be optimized away. But it isn't -- instantiating that exception on the stack is very clearly generating instructions on VS2015 and GCC 5.3. While this is not a huge deal, I don't like it so one way I can think to fix this is to conditionally compile out the catch block, but that defeats the purpose of the macros in the first place. BOOST_TRY { write_ini(stream, pt, flags); } BOOST_CATCH (ini_parser_error &e) { *#ifdef BOOST_NO_EXCEPTIONS* BOOST_PROPERTY_TREE_THROW(ini_parser_error( e.message(), filename, e.line())); *#endif* } BOOST_CATCH_END Then I thought maybe I can declval a fake 'e' in the else block by redefining the macros as follows; #ifndef BOOST_NO_EXCEPTIONS #define BOOST_TRY { try { #define BOOST_CATCH(type, var) } catch(type var) { #define BOOST_CATCH_END } } #else #define BOOST_TRY { if(true) { #define BOOST_CATCH(type, var) } else if(false) { type var = boost::declval<type>(); #define BOOST_CATCH_END } } #endif This is working, but is possibly undefined behaviour. Does anyone have thoughts on that? It also requires splitting up the type from the variable name. The next step to this would be to add a third parameter for some constructor args so we can just create an exception object directly. Something like: #define BOOST_CATCH(exception_type, var, args) } else if(false) { boost::decay<exception_type>::type var args; So now the original code would look like this: BOOST_TRY { write_ini(stream, pt, flags); } BOOST_CATCH (ini_parser_error&, e, ("", "", 0)) { BOOST_PROPERTY_TREE_THROW(ini_parser_error( e.message(), filename, e.line())); } BOOST_CATCH_END This is starting to look a little nasty to me so I'm wondering if anyone has any thoughts on this? Should I stop worrying about it and just use the #ifdef? The reality is that I work in an environment without exceptions and we hit these things from time to time so I'd like to fix up as many as possible. Thanks, -- chris

2 2

media file error
by Rainer Deyke 21 Feb '16

21 Feb '16

In "CDs/Presumed Guilty Compilation": "Beyond Dwan - Need.mp3" -> "Beyond Dawn - Need.mp3" -- Rainer Deyke (rainerd(a)eldwood.com)

1 0

What's wrong with this benchmark
by Benedek Thaler 20 Feb '16

20 Feb '16

Dear Boost, In a previous mail, I introduced a container library, `double_ended`. This library has benchmarks [0]. However, the benchmarks show unexpected results. This is what I do [1]: - compile program using G++ 5.3, -O2 - remove CPU0 from kernel scheduler pool (isolcpu=0 boot flag) - disable CPU scaling - pin benchmark thread to CPU0 - in the test, create a vector - reserve memory for 1M unsigned - write a byte to each page reserved, to warm up the page table - get TSC value (machine has constant_tsc flag) - insert 1M unsigned value - get TSC value again, subtract previous value - repeat test 25 times, average results I do this with 3 containers: std::vector, boost::container::vector and double_ended::devector. While the latter two produces almost equivalent results, std::vector seriously falls behind. - No reallocation happens between the TSC sampling - Test order doesn't matter: every order produces the same results - Container size or sample count doesn't matter, same results. - The deviations of individual measures of each container is small, the performance is consistent. - I compared the produced ASM of std::vector and double_ended::devector, they are very similar, almost the same instructions in different order [2]. What do I miss here? Thanks, Benedek [0]: http://erenon.hu/double_ended/double_ended/benchmarks.html [1]: https://github.com/erenon/double_ended/blob/master/benchmark/push_back.cpp [2]: http://pastebin.com/tUL54i9f

3 11

[RFC] C++ apparently lacks a mechanism for locking ranges of a shared resource
by Raphael S Carvalho 20 Feb '16

20 Feb '16

I am very sorry if this topic is unrelated to the topics covered by this mailing list. While developing a small project which consists of exporting a blockv device via network (if you are curious: https://github.com/raphaelsc/blockv) there was the need to lock a range of a shared resource, such as a file. I searched for resources coming from C++ standard library and boost library, but I wasn't able to find anything that would fit my needs. Am I missing something? Anyway, I ended up implementing my own range locking mechanism. The implementation is quite simple, feel free to look it at: https://github.com/raphaelsc/byte-range-lock-cpp/blob/master/range_lock.hh (I made my best effort to document it well) Is there any chance that something like range_lock will be made available in the next versions of boost library? Thank you very much for reading this, Raphael Carvalho

1 0

Re: [boost] [optional] optional(Expr&&) is insufficiently constrained
by Andrzej Krzemienski 19 Feb '16

19 Feb '16

2016-02-18 23:03 GMT+01:00 Stephan T. Lavavej <stl(a)exchange.microsoft.com>: > Hi, > > A user reported a bug (VSO#191303/Connect#2351203, see [1]) using > Boost.Optional with MSVC 2015 Update 2. The original test case involved a > minor bug in VC's tuple, which I'll look into fixing in the future > (specifically, N-tuples recursively construct (N - 1)-tuples, in a way > that's visible to overload resolution). However, there is also a bug in > boost::optional. > Hi, I have created a ticket abut this problem: https://svn.boost.org/trac/boost/ticket/12002 Frankly, I do not know how to implement it in a portable way (considering older compilers) without type trait boost::is_constructible. I am currently blocked on it: https://svn.boost.org/trac/boost/ticket/12003. As an aside, the "prevent_binding" stuff should probably be expressed as a > SFINAE constraint, not a static_assert. > About this remark, I am not sure. I understand that you want the constructors to be SFINAE-friendly, but at the same time I would loose the opportunity to convey a text message to the user-programmers, as to what the problem is. Now I do it with the static_assert. I wish I had the feature "delete for a reason" Optional::Optional(R&&r) = delete("because it would cause..."); Regards, &rzej

4 5

[iterator] function_output_iterator constructed from a lambda function is not assignable
by Mikhail Matrosov 19 Feb '16

19 Feb '16

Consider the following code snippet: auto f = [](int x) { std::cout << x; };auto it = boost::make_function_output_iterator(f);decltype(it) it2 = it; // Ok, copied it2 = it; // Does not compile, cannot assign! The problem is, function_output_iterator constructed in this way is not assignable, and thus does not satisfy the Iterator <http://en.cppreference.com/w/cpp/concept/Iterator> concept, which requires type to be CopyAssignable <http://en.cppreference.com/w/cpp/concept/CopyAssignable>. This is not a bug, since boost Function Output Iterator documentation <http://www.boost.org/doc/libs/1_60_0/libs/iterator/doc/function_output_iter…> clearly says <http://www.boost.org/doc/libs/1_60_0/libs/iterator/doc/function_output_iter…> : UnaryFunction must be Assignable and Copy Constructible. While assignment operator of a lambda function <http://en.cppreference.com/w/cpp/language/lambda> is deleted: ClosureType& operator=(const ClosureType&) = delete; So this behaviour is technically correct, but for me is somewhat unexpected. I think it is a perfectly reasonable desire to construct function_output_iterator given a closure produced by lambda function. It seems inconvenient to me why this use case causes a problem. Can you suggest a workaround for this situation? Or maybe a way of improving function_output_iterator to overcome this issue? Personally, I came up with a trick to fix this in a situation, when I'm sure iterator and its copies won't outlive the closure object. In this case we may wrap closure with std::ref: auto it = boost::make_function_output_iterator(std::ref(f)); This works quite fine, but obviously is not always possible. Another options is to store closure in std::function: std::function<void(int)> f = [](int x) { std::cout << x; }; This also works fine and is possible in most contexts, but causes related overheads. See also: http://stackoverflow.com/q/35392919/261217 ----- Best regards, Mikhail Matrosov

5 11

[type_traits] A partial implementation of boost::is_constructible
by Andrzej Krzemienski 19 Feb '16

19 Feb '16

I filed a ticket about a potential improvement of type trait boost::is_constructible: https://svn.boost.org/trac/boost/ticket/12003 I am solving the following problem. I have a one-argument perfect forwarding explicit constructor and want to constrain it only to the cases when T is constructible from U: ``` template <typename T> struct optional { template <typename U> explicit optional(U&& v, ENABLE_IF(is_constructible<T, U&&>)) {...} }; ``` I cannot afford to use the "fallback" implementation of boost::is_constructible (the one that forwards to is_convertible) because I would be constraint my constructor too much: I would rather leave it under-constrained. I do not need the full implementation of is_constructible (that would need variadic templates) because I am only using the two-argument version (and I suppose my problem is not isolated). I would like a partial implementation of is_constructible that works correctly for two arguments only; and a macro that allows me to test if it is available. I suspect that this is the common case that you use only the two-argument version, and implementing only this would handle a quite a big number of all the use cases. Is it something that fits into the library scope, or do is it something I would have to implement myself? Regards, &rzej

2 1

[range] range/concepts.hpp errors..
by Rene Rivera 19 Feb '16

19 Feb '16

I'm trying to build the auto_index tool using msvc-14 and I'm getting this error: compile-c-c++ ..\..\..\bin.v2\tools\auto_index\build\msvc-14.0\release\link-static\threading-multi\file_scanning.obj file_scanning.cpp ..\..\..\boost/range/concepts.hpp(184): error C2143: syntax error: missing ';' before '<' ..\..\..\boost/range/concepts.hpp(209): note: see reference to class template instantiation 'boost::range_detail::ForwardIteratorConcept<Iterator>' being compiled ..\..\..\boost/range/concepts.hpp(184): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int ..\..\..\boost/range/concepts.hpp(184): error C2238: unexpected token(s) preceding ';' Any ideas? -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

3 3

[STL + allocators] Bug?
by Phil Bouchard 19 Feb '16

19 Feb '16

This is about STL containers and allocators. It looks like a mistake in the STL containers but I don't think there is any possible workarounds if the Boost library is based on it. When I look at the code of GCC's std::list: template<typename _Tp, typename _Alloc> void _List_base<_Tp, _Alloc>:: _M_clear() { typedef _List_node<_Tp> _Node; _Node* __cur = static_cast<_Node*>(_M_impl._M_node._M_next); while (__cur != &_M_impl._M_node) { _Node* __tmp = __cur; __cur = static_cast<_Node*>(__cur->_M_next); #if __cplusplus >= 201103L _M_get_Node_allocator().destroy(__tmp); #else _M_get_Tp_allocator().destroy(std::__addressof(__tmp->_M_data)); #endif _M_put_node(__tmp); } } I think it should make use of the allocator's specific pointer as such: template<typename _Tp, typename _Alloc> void _List_base<_Tp, _Alloc>:: _M_clear() { typedef _List_node<_Tp> _Node; typedef typename _Alloc::rebind<_Node>::other::pointer _NodePtr; _NodePtr __cur = static_cast<_NodePtr>(_M_impl._M_node._M_next); while (__cur != &_M_impl._M_node) { _NodePtr __tmp = __cur; __cur = static_cast<_NodePtr>(__cur->_M_next); #if __cplusplus >= 201103L _M_get_Node_allocator().destroy(__tmp); #else _M_get_Tp_allocator().destroy(std::__addressof(__tmp->_M_data)); #endif _M_put_node(__tmp); } } Meanwhile I don't think there is any workaround possible for this for use of an allocator with specific pointer in Boost?

3 4

flyweight - gsoc idea - multikey-value flyweight
by Vicente J. Botet Escriba 19 Feb '16

19 Feb '16

Hi Joaquin, I have a use case where I have several keys to the same flyweight. I was trying to associate a multi-index as factory, but I don't see how it could be done. I believe that I would need something like a multikey_value<Value, KeyExtractor1, KeyExtractor2> where KeyK should be deduced from KeyExtractorK. Have you found this use case already? Do you think this could be a good GSoC project? Best, Vicente

3 9

[optional] optional(Expr&&) is insufficiently constrained
by Stephan T. Lavavej 18 Feb '16

18 Feb '16

Hi, A user reported a bug (VSO#191303/Connect#2351203, see [1]) using Boost.Optional with MSVC 2015 Update 2. The original test case involved a minor bug in VC's tuple, which I'll look into fixing in the future (specifically, N-tuples recursively construct (N - 1)-tuples, in a way that's visible to overload resolution). However, there is also a bug in boost::optional. Here's a reduced test case, which contains the relevant parts of boost::optional, and doesn't involve that bug in VC's tuple: C:\Temp>type meow.cpp #include <tuple> #include <type_traits> #include <utility> using namespace std; struct none_t { }; template <typename T> struct optional { T thing; optional(none_t) : thing() { } template <typename Expr, typename = typename enable_if< !is_same<typename decay<Expr>::type, none_t>::value #ifdef FIX && is_constructible<T, Expr>::value #endif >::type> explicit optional(Expr&& expr) : thing(forward<Expr>(expr)) { } }; int main() { tuple<none_t> one{}; tuple<optional<double>> two(one); } C:\Temp>cl /EHsc /nologo /W4 meow.cpp meow.cpp meow.cpp(22): error C2440: 'initializing': cannot convert from 'std::tuple<none_t>' to 'double' [...context...] C:\Temp>cl /EHsc /nologo /W4 /DFIX meow.cpp meow.cpp C:\Temp> This is happening because I implemented N4387 (see [2]) and the Proposed Resolution for LWG 2549 (see [3]). The PR is required to implement N4387 safely. The direct-init of two from one is attempting to select tuple's converting copy ctor (which N4387 marks as implicit, because optional's constructor from none_t is implicit). However, LWG 2549 additionally constrains the converting copy ctor. In English, when the source is tuple<A> and the destination is tuple<B>, LWG 2549 determines whether A is constructible from tuple<B>. If it IS, then the converting copy ctor vanishes, so that tuple's perfect forwarding ctor (tuple(UTypes&&...)) can construct A from tuple<B>. Alternatively, if A ISN'T constructible from tuple<B>, then the perfect forwarding ctor SFINAEs away while the converting copy ctor is permitted to participate, so A is constructed from the B within the tuple<B>. The boost::optional bug is that optional(Expr&&) isn't sufficiently constrained, so it appears to be constructible (via is_constructible) from tuple<none_t>, even though the definition will explode. So LWG 2549 makes tuple's converting copy ctor vanish, and we end up attempting to construct optional<double> from tuple<none_t> which is doomed. This is NOT a problem with LWG 2549's Proposed Resolution, NOR is it a problem in VC 2015 Update 2's tuple (which has correctly implemented this, at least for the 1-tuple case, as previously mentioned). The fix that should be applied to boost::optional is to constrain optional(Expr&&) based on whether its definition will compile. (This is inherently safe, because it just makes is_constructible report accurate answers, and doesn't affect code that previously compiled.) WG21 has (gradually) taught pair/tuple to do this (constructors are now constrained on is_constructible for elements, and additionally is_convertible when they care about implicitness; previously they didn't ask is_constructible). The relevant code in optional.hpp is: template<class Expr> explicit optional ( Expr&& expr, BOOST_DEDUCED_TYPENAME boost::disable_if_c< (boost::is_base_of<optional_detail::optional_tag, BOOST_DEDUCED_TYPENAME boost::decay<Expr>::type>::value) || boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<Expr>::type, none_t>::value >::type* = 0 ) : base(boost::forward<Expr>(expr),boost::addressof(expr)) {optional_detail::prevent_binding_rvalue_ref_to_optional_lvalue_ref<T, Expr&&>();} Unlike my reduced repro (where is_constructible<T, Expr> is the constraint corresponding to thing(forward<Expr>(expr))), I can't suggest an exact fix without knowing what optional_base's constructor is going to do with the provided arguments. As an aside, the "prevent_binding" stuff should probably be expressed as a SFINAE constraint, not a static_assert. Thanks, STL [1] https://connect.microsoft.com/VisualStudio/feedback/details/2351203/vc14-2-… [2] http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4387.html [3] http://cplusplus.github.io/LWG/lwg-active.html#2549

1 0

[Boost.Geometry] Extend spatial predicates to 1D segments?
by Lukas Barth 18 Feb '16

18 Feb '16

Hi, I'm using the rtree in Boost.Geometry to store one-dimensional intervals (as segments of one-dimensional points). There may be better suited libraries out there for this task, but I had Boost.Geometry in my project for some 2D-Rtree anyways, and since it is generic, it should be up to the task. I needed to query the 1D segments in the rtree for overlaps and got a nasty looking "not implemented" error when trying to compile. Basically, this is what I tried to do: typedef bgm::point<double, 1, coordinate_system_type> Point1D; typedef bgm::segment<Point1D> Interval; typedef bgi::rtree<Interval, bgi::quadratic<3>> Tree; mytree.query(bgi::intersects(make_interval(from,to))); (where "make_interval" is a helper that returns an interval from two doubles) Digging through the Boost.Geometry code (and I won't claim I fully understood the template magic), I found in /usr/include/boost/geometry/algorithms/detail/disjoint/linear_linear.hpp the following piece: template <typename Segment1, typename Segment2> struct disjoint<Segment1, Segment2, 2, segment_tag, segment_tag, false> : detail::disjoint::disjoint_segment<Segment1, Segment2> {}; And, more importantly, I did not find a similar piece of code with a "1" as third template parameter. Thus, I assume that the 'disjoint' predicate is just not implemented for one-dimensional segments. I added that predicate for my project, and now I'm wondering whether a full set of spatial predicates would be desirable for one-dimensional segments. In other words: If I came up with a patch adding those predicates, would it be considered? Regards, Lukas

3 2

[gsoc16] [Boost.GIL] gsoc idea - further development on Boost.GIL
by Christopher Harpum 18 Feb '16

18 Feb '16

Dear Boost, Pre-warning, this is my first time actively engaging in the mailing list - I primarily stick to the archives - so excuse me for anything non-conformat. I'm a student looking to forward a proposal regarding further development of Boost.GIL. Namely: - Cleaning up some bugs / oversights within the current review branch (lack of colour-conversion profiles for certain formats, uninitialized values resulting in UB for BMP palette alpha channels, etc.) - Fulfilling additional features and clean-up, as requested during the formal review (2010) http://lists.boost.org/boost-announce/2011/01/0281.php - Looking into further development of the io_factory proposal for run-time file format detection (http://stlab.adobe.com/wiki/index.php/GIL_File_Format_Import/Export_Factory ,POC implementation https://github.com/stlab/adobe_platform_libraries/tree/master/adobe/gil/exte nsion/asl_io) I use Boost.GIL extensively within my projects, so I've had a reasonable amount of time to get accustomed to the code-base and believe this will help me achieve these goals. I understand that the project has been undergoing a period of inactivity, so I'm not sure whether this proposal would find a suitable mentor, or if it will be of interest for a GSOC project. I hope to further discussion of this proposal prior to submitting anything formal, though I'm not fully aware of the procedures for independent submissions. Regards, Chris

2 1

[MSM] Is there any interest in C++14 Boost.MSM-eUML like library which compiles up to 60x quicker whilst being a slightly faster too?
by Krzysztof Jusiak 18 Feb '16

18 Feb '16

Dear Boosters, I have recently released 1.0.0 version of experimental C++14 Boost.MSM-lite. Your scalable C++14 header only eUML-like meta state machine library with no dependencies, which outperform Boost.MSM - eUML in: - faster compilation times - up to 60x times faster! - smaller executable size - up to 15x smaller - slightly better performance - smaller memory usage - short error messages Check it out yourself online! http://boost-experimental.github.io/msm-lite/examples/index.html#hello-world Performance Results: http://boost-experimental.github.io/msm-lite/overview/index.html#performance Source code: https://github.com/boost-experimental/msm-lite Documentation: http://boost-experimental.github.io/msm-lite Any feedback is more than welcome! Cheers, Kris

7 58

GSOC 2016
by Boldy Happy 18 Feb '16

18 Feb '16

Hello!I would like to know if Boost is participating in GSOC 2016.Please excuse if me if I made a mistake by sending this kind of email as I am just a beginner. Thanks in advance!

1 0

Interest in double ended containers
by Benedek Thaler 18 Feb '16

18 Feb '16

Dear Boost, I'd like to draw attention to my double_ended library, founded by GSoC 2015. It provides two containers, briefly described below. Given there's interest, I'd like to propose this library later. Documentation: http://erenon.hu/double_ended/ Source: https://github.com/erenon/double_ended Short overview: `devector` is a hybrid of the standard vector and deque containers, as well as the `small_vector` of Boost.Container. It offers cheap (amortized constant time) insertion at both the front and back ends, while also providing the regular features of `std::vector`, in particular the contiguous underlying memory. In contrast to the standard vector, however, `devector` offers greater control over its internals. Like `small_vector`, it can store elements internally without dynamically allocating memory. `batch_deque` is very similar to the standard `deque`, with a slight twist. It lets you specify its segment size: The size of the contiguous memory segments it uses to store its elements. This provides a consistent layout across platforms, and lets you iterate over the segments with batch operations. Thanks, Benedek

4 4

[block_ptr] Use case bug
by Phil Bouchard 18 Feb '16

18 Feb '16

In trying to anticipate all possible use cases, I think I have found a bug. Please let me try to fix it, but this is not so simple so it'll take some time.

1 1

[githelp]
by Rene Rivera 17 Feb '16

17 Feb '16

How can I find out what changes are not merged from develop to master, for all subrepos, but only changes I've made? -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

3 3

Removal of boost::basic_string_ref (in favor of basic_string_view)
by Marshall Clow 17 Feb '16

17 Feb '16

I have just removed boost::basic_string_ref from the develop branch, and updated the specializations to use basic_string_view. Code that uses boost::string_ref (and wstring_ref) should continue to work as before. The basic_string_view class better matches what the standards committee is doing and has WAY more constexpr support. I'll be watching the testbots for results, but I believe that the only part of boost that was using basic_string_ref was Boost.Log, and that was switched over to basic_string_view in December. -- Marshall

2 1

Boost.Operators issue: polluting namespace of caller through argument-dependent lookup
by John M. Dlugosz 17 Feb '16

17 Feb '16

Here's the problem I ran into http://stackoverflow.com/questions/34449254/how-is-argument-dependent-looku… |usingstd::tr1::shared_ptr; ||usingstd::tr1::make_shared;| |shared_ptr<Dog>Gamma::knockout (constHotel&target){Eggsoftboiled (target.ID);softboiled.sequence ^=0x40000000;returnmake_shared<Dog>(softboiled,target.kin,Frank::myself());} | The arguments to the constructor passed through make_shared are of types |Able::Bravo::Charlie::Egg&,constuint32_t&,constFrank&| The use of make_shared is finding boost::make_shared as well as std::make_shared. The program doesn't use boost::shared_ptr and shouldn't need to know about it. It turns out that Frank is derived privately from boost::totally_ordered1 (and and Egg from boost::totally ordered). Some Boost header that's being used in this translation unit just happens to pull in Boost's shared_ptr stuff. It ends up effectively polluting the namespace of possible calls involving these types, thanks to argument-dependent lookup. Furthermore, which Boost headers include which will change from version to version. I have this problem show up much more in Boost 1.60 than I have in Boost 1.59. There is no easy way around it beyond qualifying the call make_shared, and I specifically want to avoid that so I don't litter the program with tr1's (this varies by compiler and version as to whether tr1 is required, prohibited, or optional, so I want it in one place.) I believe the proper thing to do, which is a very simple fix actually, is to define the mix-in classes like totally_ordered (and other things from Boost.Operators in particular) in a unique inner namespace, and then make aliases in the boost namespace where they are published as being found. namespace boost { *namespace inner_name_1 { * template<typename T, Typename U> partially_ordered { ⋯ }; // the entire guts of Boost.Operators can go here, I think. *} // end of inner isolating namespace** ** ** using inner_name_1::partially_ordered;* // etc. } This inner isolation technique should be SOP for any classes that are meant to be inherited from by user (non-Boost library) code. It would not hurt to also isolate classes that match the names of std library code, in general! This would, in general, prevent the libraries from interfering with each other and surprises popping up when using std components and pulling in Boost headers. —John ||

4 12

remove cached feature checks
by Oliver Kowalke 17 Feb '16

17 Feb '16

Hi, how is it possible to remove the cached feature checks? Boost.Config Feature Check: cxx11_constexpr : no (cached) b2 -a toolset=clang cxxflags="-std=c++11" does not re-check the features. Oliver

4 4

[block_ptr] 20% speed boost
by Phil Bouchard 17 Feb '16

17 Feb '16

> If I try out the latest modifications and I disable the threads then on > Linux I have: > > make: > auto_ptr: 2458626 ns > shared_ptr: 2685224 ns > block_ptr: 28300624 ns > > new: > auto_ptr: 2383605 ns > shared_ptr: 4992185 ns > block_ptr: 7979659 ns So I just added a specialization of the pool for GCC x86 and now block_ptr<> speeds up by 20%: make: auto_ptr: 2511658 ns shared_ptr: 2695469 ns block_ptr: 22547960 ns new: auto_ptr: 2369312 ns shared_ptr: 4991352 ns block_ptr: 6443925 ns Thanks, -Phil

1 2

[Fit] Purpose and Use Cases
by Artyom Beilis 17 Feb '16

17 Feb '16

Hello, Before the formal review begins I would really like to understand the purpose of Boost.FIT It isn't clear to me from the documentation what are the real world use cases? What can't be done today (for example composition) with simple C++11 lambdas? I'd love to see several real world examples and use cases of Boost.FIT - because at least for me I don't really understand why it is useful. Artyom

4 3

Re: [boost] [block_ptr] Request for a review manager
by Bjorn Reese 17 Feb '16

17 Feb '16

On 02/04/2016 03:02 AM, Phil Bouchard wrote: > On the other hand I code completed the deterministic block_ptr in 2011 > and I am wondering if there is anything I am missing to get it through > the review process because this is one of the most important subject in > computer science: > https://svn.boost.org/svn/boost/sandbox/block_ptr/libs/smart_ptr/doc/index.… Do you have any performance measurements comparing block_ptr<T> with shared_ptr<T>? Btw, in the overview section you claim that shared_ptr<T> has to manage counters when it is dereferenced. I am not entirely sure that is correct.

3 7

Boost.Python gsoc project
by Barun Parruck 16 Feb '16

16 Feb '16

Hi! I'm a student looking to get involved with the open source through boost. I was looking through the gsoc projects, and the one involving Boost.python, by Stefan Seefeld piqued my interest! I was wondering what sort of student you'd be looking for for the project, more details about what the project would entail, and what sort of programming competency test I would have to pass.

2 1

stupid github question
by Robert Ramey 16 Feb '16

16 Feb '16

I want to add a contributer to the serialization library - but I can't figure out how to do this on github. I believe this has something to do with the fact that the serialization library is a sub project. It shouldn't be a big deal as I see there are already 31 contributors on the list - many of whom I don't recognise. Robert Ramey

2 3

Alternative remove, erase, and partition algorithms
by Brent Friedman 15 Feb '16

15 Feb '16

Hello, I'd like to propose the following for inclusion in Boost.Algorithm. *semistable_partition* partitions a range into 'good' and 'bad' elements, as partition. 'Good' elements maintain their order, while 'bad' elements are left in unspecified order. stable_partition has either linear additional storage or performs 3NlogN move operations, whereas semistable_partition has constant memory overhead and at most 3N move operations. Requires forward iterators. *unstable_remove ( _if )* removes elements from a range but without maintaining element order. Performs at most N/2 moves as compared to N for remove. Requires bidirectional iterators. *unstable_erase* erases an iterator or range from a container ( as vector::erase ) without maintaining element order. Intuitively, this fills in the hole created by the erase operation by moving elements from the end. Limited to containers with bidirectional iterators (possibly random-access). The following documents describe and explore these algorithms: https://groups.google.com/a/isocpp.org/forum/#!topic/sg14/2uwOmXWqa2E (unstable_erase, unstable_remove) https://iterator.wordpress.com/2016/01/31/algorithms_0/ (unstable_remove, semistable_partition) I have been pursuing standardization, but it seems like there is value in getting community experience with these algorithms first in order to make for easier justification. -Brent Friedman

1 0

[block_ptr] Works on MSVC + Boost.Pool bug
by Phil Bouchard 15 Feb '16

15 Feb '16

It looks like I was able to fix a bug which makes it run correctly under MSVC 2015 Express. Although I do have a crash in the boost::pool: Project2.exe!boost::simple_segregated_storage<unsigned int>::try_malloc_n(void * & start, unsigned int n, unsigned int partition_size) Line 333 C++ Project2.exe!boost::simple_segregated_storage<unsigned int>::malloc_n(unsigned int n, unsigned int partition_size) Line 363 C++ Project2.exe!boost::pool<boost::default_user_allocator_new_delete>::ordered_malloc(unsigned int n) Line 801 C++ Project2.exe!boost::singleton_pool<boost::detail::bp::pool,1,boost::default_user_allocator_new_delete,boost::details::pool::null_mutex,32,0>::ordered_malloc(const unsigned int n) Line 149 C++ Project2.exe!boost::detail::bp::pool::allocate(unsigned int s) Line 148 C++ Project2.exe!boost::detail::bp::block<int>::operator new(unsigned int s) Line 283 C++ Project2.exe!boost::detail::bp::make_block<int,int>(const int & t0) Line 520 C++ > Project2.exe!main() Line 119 C++ When I try this example: https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test2… Thanks, -Phil

1 1

Re: [boost] [block_ptr] Request for a review manager
by Peter Dimov 15 Feb '16

15 Feb '16

> Phil Bouchard wrote: > > > I added the new repository with the right folder structure: > > https://github.com/philippeb8/block_ptr > > You should update this to work with the latest Boost, because currently > block_base is abstract as it doesn't implement > > virtual void * get_untyped_deleter() = 0; It also doesn't work with -DBOOST_DISABLE_THREADS, which makes it inconvenient to test as it requires Boost.Thread.

3 7

[dll] dbghelp.hpp in detail/winapi
by Andrey Semashev 14 Feb '16

14 Feb '16

Hi, I've noticed that Boost.Dll provides boost/detail/winapi/dbghelp.hpp header. boost/detail/winapi is the directory of Boost.WinAPI submodule, and I generally don't expect anyone else putting his header in that directory. Could dbghelp.hpp be moved somewhere inside boost/dll?

3 5

Re: [boost] expected/result/etc
by Emil Dotchevski 13 Feb '16

13 Feb '16

On Wed, Jan 27, 2016 at 10:49 PM, Michael Marcin <mike.marcin(a)gmail.com> wrote: > So looking a few of these libraries/proposals I have a few things I'm > interested in. > > - Is it at least as good as a simple hand-rolled solution? > - Can you transport error codes through layers without knowing specifics > of an error? > > For the second Niall's outcome/result handles very well I think. > std::error_code and std::exception_ptr transport is good enough for almost > any reasonable type agnostic error transport. > Have you considered using Boost Exception? It lets you add arbitrary data to exception objects, even after they have been thrown, regardless of their type -- see http://www.boost.org/doc/libs/release/libs/exception/doc/error_info.html. The general idea is to adopt a strategy where the exception objects are augmented with any, even platform-specific relevant data, which then the catch site can analyze to choose the correct handling. Cheers, Emil

9 69

[type_traits] ICE with msvc-12.0
by Steven Watanabe 13 Feb '16

13 Feb '16

AMDG I'm getting boost\type_traits\common_type.hpp(43): fatal error C1001: An internal error has occurred in the compiler. (compiler file 'msc1.cpp', line 1325) To work around this problem, try simplifying or changing the program near the locations listed above. which makes this toolset basically unusable. Oddly enough, I don't see this error in the regression matrix. Does anyone know what's up with this? > cl Microsoft (R) C/C++ Optimizing Compiler Version 17.00.50727.1 for x86 Copyright (C) Microsoft Corporation. All rights reserved. scratch.cpp: #include <boost/type_traits/common_type.hpp> int main() { boost::type_traits::common_type<int, char, long>::type x = 0; } > cd libs/type_traits > git log commit 1f3a3a1553dc316ed002354dce3ba3f081b2e102 Author: jzmaddock Date: Wed Jan 13 10:50:22 2016 +0000 Fixes for older GCC versions, see issue 11904. ... > dir boost ... 02/25/2015 08:26 PM <JUNCTION> type_traits [...\libs\type_traits\include\boost\type_traits] ... In Christ, Steven Watanabe

2 1

[regression] Winapi submodule tests missing
by Andrey Semashev 13 Feb '16

13 Feb '16

Hi, The winapi submodule tests are missing from the test matrix, although the status/Jamfile.v2 lists it. This is both on develop and master. Is there something I should do to make the tests appear?

2 5

Re: [boost] expected/result/etc
by Giovanni Piero Deretta 13 Feb '16

13 Feb '16

On 12 Feb 2016 11:20 a.m., "Niall Douglas" <s_sourceforge(a)nedprod.com> wrote: [...]. > > LLVM, for the record, has implemented a very similar "universal" > exception handling mechanism which allows exception throws to > traverse language boundaries within LLVM, and my great hope is that > once LLVM becomes universal on POSIX platforms someone will go ahead > and replace signals with structured exception handling. As far as I know LLVM simply implements unwinding as mandates by the Itanium ABI, which is already the de facto standard on many unices. Is this what you are referring to? This is completely orthogonal with handling OS/machine exceptions (segfaults, division by zero, etc..). And with right compiler and flag there are ways to convert (synchronous) signals to exceptions. This actually required to support the semantics of languages other than the C family, like Java and Ada. Notably, it doesn't actually work with LLVM, but it does with gcc. -- gpd

2 1

[filesystem] temp_directory_path and Android devices (repost)
by doodad-js Admin 12 Feb '16

12 Feb '16

(sorry for the repost, but someone told me that I should include "filesystem" in the subject) Hi, I have read the specs (http://www.boost.org/doc/libs/1_60_0/libs/filesystem/doc/reference.html#tem p_directory_path) and found the following issues with Android devices: - It should first try to get the application's cache directory from the API level 1 "getCacheDir" so that temporary files created by the application can be easily and automatically removed. - The function fails back to the hard coded value "/data/local/tmp". But I think it should use the environment variable "ANDROID_DATA" when available and append "/local/tmp" to it. - The "/data/local/tmp" folder is denied access on my Android device. I don't have any other suggestion than the application's cache folder like I first mentioned. I'm not a core developer and the information provided on this email maybe erroneous or incomplete. My apologies if I'm entirely wrong. Thanks, Claude Petit

1 0

Contribution to Boost as Developer
by aman kumar singh 11 Feb '16

11 Feb '16

Developers, I am Aman Kumar Singh,Senior Year,NIT Mizoram,India(Computer Science and Engineering).I am new to open source development. I like coding especially in C++.I have 6 years of working experience in C++.I am very much interested in contributing to open source development especially in Boost.I want to apply for Google Summer of Code 2016 in future.Can somebody help me out.I am ready to dedicate my full time to it once I get aware of the system fixing bugs and further contributing to big projects. I am left with very less time for GSoC and this time I want to be part of it.Please help me out. Thanking you, Aman Kumar Singh, NIT Mizoram, India

1 0

problem with ASIO
by Juan Dent 10 Feb '16

10 Feb '16

Thank you so much Bjorn Reese!! you solved my problem with ASIO. My instincts were correct in that the stream was destroying the std::cout. ::dup() solves this. Best regards, Juan

1 0

Re: [boost] Problem with ASIO
by Bjorn Reese 10 Feb '16

10 Feb '16

On 02/10/2016 02:27 AM, Juan Dent wrote: > posix::stream_descriptor stream{ioservice, STDOUT_FILENO}; Here you take over ownership of stdout, so it will be closed by the stream destructor. A quick fix is to pass a copy of the file descriptor with ::dup(STDOUT_FILENO) as shown in the posix_chat_client.cpp example.

1 0

temp_directory_path and Android devices
by doodad-js Admin 10 Feb '16

10 Feb '16

Hi, I have read the specs (http://www.boost.org/doc/libs/1_60_0/libs/filesystem/doc/reference.html#tem p_directory_path) and found the following issues with Android devices: - It should first try to get the application's cache directory from the API level 1 "getCacheDir" so that temporary files created by the application can be easily and automatically removed. - The function fails back to the hard coded value "/data/local/tmp". But I think it should use the environment variable "ANDROID_DATA" when available and append "/local/tmp" to it. - The "/data/local/tmp" folder is denied access on my Android device. I don't have any other suggestion than the application's cache folder like I first mentioned. I'm not a core developer and the information provided on this email maybe erroneous or incomplete. My apologies if I'm entirely wrong. Thanks, Claude Petit

1 0

[ANN] build2 - C++ build toolchain
by Boris Kolpackov 10 Feb '16

10 Feb '16

Hi, build2 is an open source, cross-platform toolchain for building and packaging C++ code. It includes a build system, package manager, and repository web interface. We've also started cppget.org, a public repository of open source C++ packages (where we hope to see Boost one day). This is the first alpha release and currently it is more of a technology preview rather than anything that is ready for production. We have tested this version on various Linux'es, Mac OS, and FreeBSD. There is no Windows support yet (but cross-compilation is supported). The project's page is: https://build2.org For those who need to see examples right away, here is the introduction: https://build2.org/build2-toolchain/doc/build2-toolchain-intro.xhtml Enjoy, Boris

9 19

Problem with ASIO
by Juan Dent 10 Feb '16

10 Feb '16

Hi, I have a problem with the following sample (ASIO 10, part of Boost examples): void f() { { io_service ioservice; posix::stream_descriptor stream{ioservice, STDOUT_FILENO}; auto handler = [](const boost::system::error_code&, std::size_t) { std::cout << ", world!\n"; }; async_write(stream, buffer("Hello"), handler); ioservice.run(); std::cout << "hhh\n"; } // in this line and afterwards, no output will be seen through std::out!! ( it is somehow damaged or destroyed by the destructor of the *stream* object!! std::cout << “This will not print\n"; } As explained in the line comment, when stream is destroyed some permanent damage is done to the std::out object which will not output any more after executing the code in the nested block. I believe the stream should be somehow disconnected from STDOUT_FILENO before its destruction so it does not “harm” std::out. Any ideas? Thanks!! Juan

1 0

[block_ptr] Request for a review manager
by Phil Bouchard 09 Feb '16

09 Feb '16

Greetings, As some of you might know I work full time on WebKit which in turn uses a garbage collector for its Javascript interface and quite honestly a garbage collector is not ready for a commercial release unless you have a lot of CPU juice. So a garbage collector is unacceptable. On the other hand I code completed the deterministic block_ptr in 2011 and I am wondering if there is anything I am missing to get it through the review process because this is one of the most important subject in computer science: https://svn.boost.org/svn/boost/sandbox/block_ptr/libs/smart_ptr/doc/index.… Please let me know if you are interested for me to present it and answer questions live. Sincerely, -Phil www.unifiedfieldtheoryfinite.com

6 17

recompile with -fPIC
by Marwa Refaie 09 Feb '16

09 Feb '16

Hi I try to compile "cdec" translation package , I been stuck in this error : ______________________________________________________________________________ /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/libboost_system.a(error_code.o): relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a shared object; recompile with -fPIC/usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/libboost_system.a: error adding symbols: Bad value collect2: error: ld returned 1 exit status error: command 'g++' failed with exit status 1______________________________________________________________________________ I red solution like bjam boost without debug or specifiy -fPIC !!! Any help to apply any solution ?? How should I fix plz ?? Marwa N. Refaie

1 0

[smart_ptr] Interest in the missing smart pointer (that can target the stack)
by Noah 09 Feb '16

09 Feb '16

Hi all, I'm new here. Here goes: I propose a new smart pointer called, say "registered_ptr", that behaves just like a native C++ pointer, except that its value is (automatically) set to null_ptr when the target object is destroyed. This kind of smart pointer already exists and is being used in the form of, for example, QPointer and Chromium's WeakPtr (http://doc.qt.io/qt-5/qpointer.html and https://code.google.com/p/chromium/codesearch/#chromium/src/base/memory/wea…) although those implementations only apply to a specific set of object types. There's also std::experimental::observer_ptr (http://en.cppreference.com/w/cpp/experimental/observer_ptr) which seems to be trying to serve a similar purpose, but with none of the functionality. This might be as far as you need to read to decide if you think it's a good idea or not. The rest of this (kind of long) post addresses some of the details and motivation. It's instructive to compare this "registered_ptr" with (std::)shared_ptr. Both have a (modest) performance cost, although registered_ptr's performance cost is significantly lower, as will be discussed later. Both can have a significant "code safety" benefit when used for that purpose - i.e. reduce or eliminate the possibility of invalid access of an object that has already been destroyed. And both have a functional purpose other than safety or convenience (or just being a regular pointer). That functional purpose is to deal with situations when it is not easy to predict in advance (i.e. at compile time) when an object will be referenced (and stop being referenced). shared_ptr deals with these type of situations by ensuring that the object remains "alive" for as long as there are any (owning) references to the object. This assumes that the object has no "curfew". But one can imagine situations where an object needs to be destroyed at or by a certain time or event. If the object is exclusively holding an in demand resource, or security lock for example. In these cases one might prefer that late attempted references to the object fail (safely) rather than have the object's destruction delayed. registered_ptrs might be more suitable for these situations. So from this comparison it's hard to argue for the inclusion of shared_ptr and the omission of registered_ptr in the library. registered_ptr can be thought of as a kind of "non-intrusive" counterpart to shared_ptr. "But wait", you say, "shared_ptr already has a non-intrusive counterpart. Namely weak_ptr." Yes, but the difference between weak_ptr and registered_ptr is that registered_ptr is independent, not just an appendage of shared_ptr. And registered_ptr can point to stack allocated objects (just like native C++ pointers can), but at the cost of "thread safety". Referencing an object on another (asynchronous) thread's stack is inherently not safe, right? Some may be concerned with this lack of thread safety - I am not, I don't think we should be encouraging casual asynchronous object sharing - but the performance dividend of getting to put the target object on the stack rather than the heap more than makes up for it in my opinion. So I've actually already had cause to implement, and use, a version of this "registered_ptr" (I actually called it "TRegisteredPointer"), and in practice it works great. But there are, arguably, a couple of issues. Besides the thread safety (non-)issue, my implementation can only target types that can act as base classes. By default most classes can act as a base class, but native types like int, bool, etc. cannot. In my case, this is not a big issue because TRegisteredPointer is actually part of a small library that includes (safer) substitutes for int, bool and size_t that can act as base classes. The good thing is that it does seem to serve its purpose of not only being safe, but also faster than shared_ptr. Much faster when targeting stack objects as one would expect, but also faster when targeting heap objects according to my simple benchmarks (msvc2013 - Windows 7 - Haswell). My implementation can be found here: https://github.com/duneroadrunner/SaferCPlusPlus. It's in the file called "mseregistered.h". Examples of it in action can be found in the file called "msetl_example.cpp", near the end. No decent documentation yet, but the examples are commented and it should be clear what's going on. So far I've posited that the argument for registered_ptr is at least as good as the argument for shared_ptr. But let me make a further argument for why I think it's particularly important to include registered_ptr. First, let me make an argument for "safe" pointers in general. By safe pointers, I mean pointers that have zero chance of participating in a dereference to invalid memory. This will usually imply that the safe pointer will do a runtime check and throw an exception if an invalid dereference is attempted. Now, I subscribe to the C++ "trust the programmer" philosophy, so I agree that programers should have the option of avoiding these runtime checks. But security (and by extension, language safety) is so important these days that programmers should also have the option of having these runtime checks when desired. So I'm suggesting that all the smart pointers (shared_ptr, unique_ptr, etc.) come in "safe" versions as well. There is already some precedent for safe and unsafe options. For example, std::vector<> provides both the "unsafe" [] operator and the "safe" at() function. And ultimately it needs to be properly measured, but I would think that the performance cost of this kind of runtime check should be quite modest. There is plenty of opportunity for optimizing compilers to strip them out when not needed and of course these sorts of runtime checks are a favorite food of branch predictors in modern cpus right? I haven't put a lot of effort into this, but my simple benchmarks show checked dereferences being only modestly slower than unchecked dereferences. (The "msetl_example.cpp" file includes some simple benchmarks.) So why does this make registered_ptr so important? Because the "safe" version of registered_ptr would be the safe pointer with the lowest performance cost. Perhaps low enough for the safety benefits to be widely considered worth the cost. Of course the ideal would be smart pointers that could distinguish between stack allocated objects and heap allocated objects. Unfortunately, as far as I know, (standard) C++ doesn't seem to give us that facility. If we can't have those, I think we need a smart pointer that can at least accommodate stack allocated objects. Right? Noah

10 45

[Fit] Announcing Fit's formal review (March 2nd)
by paul Fultz 08 Feb '16

08 Feb '16

Dear Boost community, The formal review of the Fit library starts Wednesday, 2nd March and ends on 13th March. Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Fit is: - Modern: Fit takes advantages of modern C++11/C++14 features. It support both `constexpr` initialization and `constexpr` evaluation of functions. It takes advantage of type deduction, varidiac templates, and perfect forwarding to provide a simple and modern interface. - Relevant: Fit provides utilities for functions and does not try to implement a functional language in C++. As such, Fit solves many problems relevant to C++ programmers, including initialization of function objects and lambdas, overloading with ordering, improved return type deduction, and much more. - Lightweight: Fit builds simple lightweight abstraction on top of function objects. It does not require subscribing to an entire framework. Just use the parts you need. Fit is divided into three components: * Function Adaptors and Decorators: These enhance functions with additional capability. * Functions: These return functions that achieve a specific purpose. * Utilities: These are general utilities that are useful when defining or using functions Fit has been tested on gcc 4.6-4.9, clang 3.4-3.7, and Visual Studio 2015. For more information see: Github: https://github.com/pfultz2/Fit/tree/boost Documentation: http://pfultz2.github.io/Fit/doc/html/ I hope everyone can participate in the review. Thanks, Paul

4 3

How best to implement a bitfield in C++ 14?
by Niall Douglas 07 Feb '16

07 Feb '16

Dear Boost, As part of the AFIO v2 rewrite I've been trying to improve on how AFIO v1 did bitfields by making better use of constexpr and the type system to make usage more natural. I'd appreciate feedback on my efforts. AFIO v1 has an example of usage at https://goo.gl/oVLIjU or https://gist.github.com/ned14/9ef2a9d00da0ffc877b8 and it took the following form: enum class flag : size_t { none=0, delete_on_close=1, disable_safety_fsyncs=2 }; BOOST_AFIO_DECLARE_CLASS_ENUM_AS_BITFIELD(flag) The BOOST_AFIO_DECLARE_CLASS_ENUM_AS_BITFIELD macro declares all the sensible global overloads you'd expect, is type safe and you can use it without surprise except in one single instance: testing for emptiness. The problem is that you cannot declare as a global operator an explicit operator bool nor member functions on enums, so one cannot do if(f) though if(!f) is fine. In AFIO v1, I used if(!!f) and if(!!(f & flag::foo)) everywhere, which is fine if a little abtuse. AFIO v2's current bitfield has an example of usage at https://goo.gl/LsjSGD or https://gist.github.com/ned14/89ee39c6b8eb5254116a and it takes the following form: struct flag : bitwise_flags<flag> { flag() = default; constexpr flag(bitwise_flags<flag> v) noexcept : bitwise_flags<flag>(v) { } static constexpr auto none(){ return bit(0);} static constexpr auto delete_on_close(){ return bit(1); } static constexpr auto disable_safety_fsyncs(){ return bit(2); } }; Here the bitwise_flags<> base class does all the implementation magic, so once again you can use it without surprise except for the obvious clanger - bitfield items are now functions, so instead of the more natural: flag f(flag::disable_safety_fsyncs); flag f2(f&flag::none); f2|=flag::delete_on_close; constexpr flag f3(flag::disable_safety_fsyncs); constexpr flag f4(f3&flag::none); You are stuck with: flag f(flag::disable_safety_fsyncs()); flag f2(f&flag::none()); f2|=flag::delete_on_close(); constexpr flag f3(flag::disable_safety_fsyncs()); constexpr flag f4(f3&flag::none()); I'll admit I started this with the static constexpr flag values being member variables which always works on MSVC and on GCC and clang when the optimiser is running. Unfortunately both GCC and clang appear to be extremely conservative about when a constexpr variable is ODR-used, indeed despite my original design of an unavoidable lvalue-to-rvalue conversion intended to force ODR-used to be off both compilers go ahead and enforce ODR-used anyway which generates undefined reference errors for the storage of the static member variables :( If you'd like to read more about that, and the WG21 DR relating to [basic.def.odr], see https://stackoverflow.com/questions/8016780/undefined-reference-to-sta tic-constexpr-char/28846608#28846608. So, do Boosters think we can actually make a C++ 14 bitfield which: 1. Is typesafe, so not a C bitfield. 2. Is convenient for programmers to declare (i.e. little boilerplate in a specific bitfield declaration). 3. Works as you'd expect a bitfield to work, including bitfield::flag. 4. if(bf) works. 5. Is 100% constexpr and generates zero runtime overhead. My thanks in advance for any advice. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

6 26

expected/result/etc
by Michael Marcin 07 Feb '16

07 Feb '16

Some months ago there was a lot of discussion regarding Rust style return values for non-exceptional error handling. Did anything ever come of this? Is there a useable library? Apologies if I missed an announcement (I've been away for a bit).

7 31

[gsoc16] ATTN: Project ideas deadline 19th Feb
by Niall Douglas 07 Feb '16

07 Feb '16

Tomorrow 8th February the application period for Google Summer of Code 2016 begins, and yet we have just *one* idea on the ideas page: https://svn.boost.org/trac/boost/wiki/SoC2016 We need *plenty* more if we are to be approved again this year as a Google Summer of Code org, the deadline for which is the 19th February. So if you have some project ideas and think you could mentor a student this summer, *please* consider adding a project idea to the ideas list or stepping forward with a list of Boost libraries or topics you'd be willing to mentor. Our thanks in advance. --- Boost C++ Libraries Google Summer of Code 2016 admin https://svn.boost.org/trac/boost/wiki/SoC2016

1 0

[math] Missing constexpr statement in MPFR bindings
by Claas H. Koehler 05 Feb '16

05 Feb '16

Hi, I encountered a compiler error using gcc-5.0 with the math constants in boost 1.60.0 due to a different exception specification of math::tools::digits(): The prototype defined in math/tools/precision.hpp has a BOOST_NOEXCEPT specifier, while the implementation in math/bindings/mpfr.hpp does not have the respective specification. Adding BOOST_NOEXCEPT in math/bindings/mpfr.hpp solves the problem, i.e. compilation succeeds. I was wondering whether this is a bug or whether the error can be circumvented in another way. Regards Claas

2 1

Is there interest in Computable Calculus?
by Alexander Lauser 05 Feb '16

05 Feb '16

Hi, An arithmetic operation produces a new function using the functions in the operands and some simple expression manipulations. if I gather it right, then what you propose is basically a Computer Algebra System (i.e., a system for manipulating reals by symbolic expressions). What specifically would the goal of the library be? Best, Alex

2 5

updated version of safe integer library
by Robert Ramey 05 Feb '16

05 Feb '16

I've updated my safe integer library. Pointers to the most recent documentation and code can be found at www.blincubator.com . Or one can use documentation http://htmlpreview.github.io/?https://github.com/robertramey/safe_numerics/… repository: https://github.com/robertramey/safe_numerics I've resolved added more tests. added more examples and explanation of them added facilities to enforce a guarantee of zero runtime penalty added new section to the documentation of the above added more documentation regarding the library implementation. and other stuff. There is still a little more to do. But there is nothing that I know about that would prevent users from using this library right now to implement guaranteed correct integer arithmetic in their applications. Of course I'm interested any feedback and/or observations anyone want's to offer. Robert Ramey

5 13

[iterator] Boost zip iterator
by Claas H. Koehler 05 Feb '16

05 Feb '16

First of all thanks for implementing the support of std::pair with the zip iterator in boost 1.60. While testing the feature, I noticed that it is necessary to add the following include #include <boost/fusion/adapted/std_pair.hpp> before code using the zip iterator with std::pair. Just wondering if this was intentional behaviour or if the include should happen directly in zip_iterator.hpp. Anyway, the feature works great and is a real improvement for our projects. Regards Claas

1 0

Transferring the boost-qvm github repository to Boost
by Emil Dotchevski 03 Feb '16

03 Feb '16

Hello, Ron Garcia, one of the Boost Review Wizards, has directed me to ask the mailing list about the exact procedure for transferring the boost-qvm github repo to Boost. I believe I need to have some kind of permissions to be able to use the built-in github repo transferring mechanism. Thanks, Emil

2 1

[Math] Statistical Distributions parent distribution class
by Clancy Emanuel 01 Feb '16

01 Feb '16

In the Statistical Distributions section of Boost.Math there is a future directions link that talks about an "any_distribution" class. Is this planned for a future release? Is anyone working on this? I came across a need for this when writing a lambda to find the pdf of a certain value of a random variable. It would be helpful for iterating over a vector of random variables whose distributions are not the same.

2 1

Adding Metaparse to the master branch
by Abel Sinkovics 31 Jan '16

31 Jan '16

Hi, I've created a pull request to add the Metaparse tests to the Boost regression tests (#113) on the develop branch (Metaparse itself is already part of the develop branch, only the regression test integration is missing). I would like Metaparse to be added to the master branch as well. I have created pull request #112 for that. Please let me know what else is needed. Thanks, Abel

4 7

[tools/GSoC] static code analysis?
by Oliver Kowalke 30 Jan '16

30 Jan '16

Hi, would it be possible to provide a boost-tool or maybe a boost-GSoc project that enables static code analysis for boost developers? clang-tidy ( http://clang.llvm.org/extra/clang-tidy/) could be used for this purpose. Oliver

4 6

Re: [boost] [coroutine] x86 msvc11 stack corruption
by AVZ 29 Jan '16

29 Jan '16

Just want to share workaround which work for our company. (Fiber fix was not acceptable for that application) Debugging differences in make_fcontext between 1.53 vs 1.57, I found that in 1.53 context area is cleanned with 0, but not in 1.57. So we added explicit clear after line 100 in make_x86_64_ms_pe_masm.asm: sub rax, 0128h * ; memset context area pxor xmm0, xmm0 movaps [rax+008h], xmm0 movaps [rax+018h], xmm0 movaps [rax+028h], xmm0 movaps [rax+038h], xmm0 movaps [rax+048h], xmm0 movaps [rax+058h], xmm0 movaps [rax+068h], xmm0 movaps [rax+078h], xmm0 movaps [rax+088h], xmm0 movaps [rax+098h], xmm0 movaps [rax+0a8h], xmm0 movaps [rax+0b8h], xmm0 movaps [rax+0c8h], xmm0 movaps [rax+0d8h], xmm0 movaps [rax+0e8h], xmm0 movaps [rax+0f8h], xmm0 movaps [rax+108h], xmm0 movaps [rax+118h], xmm0 * ; third arg of make_fcontext() == address of context-function mov [rax+0118h], r8 With that we are getting same behavior as 1.53 - no crash on DLL load. Thanks, AZ -- View this message in context: http://boost.2283326.n4.nabble.com/coroutine-x86-msvc11-stack-corruption-tp… Sent from the Boost - Dev mailing list archive at Nabble.com.

1 0

[Iterator] [PR] Fix for documentation #8010
by Nathan Wilson 29 Jan '16

29 Jan '16

Hi, As a followup to my inquiry about maintaining the Iterator Library about a month back, I wanted to create PR for a simple documentation fix. So, here it is: https://github.com/boostorg/iterator/pull/21 Please let me know if there are any thoughts and/or if I'm doing something incorrectly. Thanks! Nate

2 2

Interest in some Algorithms
by Dean Michael Berris 29 Jan '16

29 Jan '16

Hi Boost! It’s been a while, I hope you all have been doing well. I wanted to ask whether anybody’s interested in a couple of algorithms, to be made part of the Boost.Algorithm library. One is tentatively named ‘set_inplace_difference' which has the following synopsis: template <class I1, class I2> I1 set_inplace_difference(I1 f1, I1 f2, I2 f2, I2 l2); template <class I1, class I2, class C> I1 set_inplace_difference(I1 f1, I1 f2, I2 f2, I2 l2, C comp); It’s essentially a set_difference which re-uses the storage of the range [f1, l1). It takes elements from [f1, l1) that are in [f2, l2) and moves them to [p, l1) where p is the partition point (or the new “end”). This is best used in conjunction with “erase” on vectors and/or std::deque. These algorithms return p. Another is tentatively named ‘set_inplace_intersection’ which instead of the above which does the difference, does an intersection instead. Requirements on I1 and I2 are that they are RandomAccess iterators, and that they are sorted. I haven’t figured out whether partially-sorted is a sufficient condition. I also haven’t figured out whether it would work for weaker iterator classes, but so far my implementation relies on std::lower_bound and std::upper_bound. If there’s enough interest, I can prepare a pull request after going through my employer’s open-source patching process. Looking forward to hearing your thoughts! Cheers

4 7

C++Now 2016 Registration is Open
by Jon Kalb 28 Jan '16

28 Jan '16

Boost Developers, Registration is now open for this year¹s C++Now (put on by Boost). http://cppnow.org/2016-conference/announcements/2016/01/28/registration-is-o pen.html The conference has sold out the last three years and is expect to do say again this year. Do not put off registering. Note that session submitters should not register until they receive instructions from Marshall Clow, our conference registrar. See you in Aspen! Jon

1 0

Interest in library for nested containers?
by Alberto Marnetto 28 Jan '16

28 Jan '16

Hello, is there interest in adding a library for nested containers (including a flattening view, a function counting the scalar elements etc.) to Boost? A working version is available at https://github.com/AlbertoMarnetto/multidim . If the concept and the interface are suitable for a submission – in particular if the requirement of a C++11 compiler is acceptable and the small number of functionalities is not a problem – I can proceed to restructure the library to meet Boost's style guidelines. Regards, Alberto Marnetto

2 2

QuickBook generate table of references?
by Nat Goodspeed 27 Jan '16

27 Jan '16

I have a biggish document consisting of a number of different .qbk files -- big enough to make it unreasonable to start over with a different toolchain. I would like to mark up particular methods of particular classes in such a way that QuickBook will produce a consolidated list of links to those methods. I read a little about DocBook being able to generate tables of figures, etc., but between QuickBook syntax and the final output document, my mental model has a big "then a miracle occurs" cloud. Will someone please show me how this is achieved? Thank you!

4 8

Query regarding time complexity requirements of iterators in custom container
by Soul Studios 26 Jan '16

26 Jan '16

Hi there- currently working on Colony, last version I'm working on has achieved constant-time(amortised) time-complexity for iterator operations, except for the random-access operators (+, -, +=, -=, [], >, <, >=, <=). It's not possible to make these constant-time due to the nature of the algorithms and structure of container. Ion pointed out to me that there is an obscure C++ requirement for iterators that all operations be constant-time. Given this, is it worth keeping these in Colony before submitting to Boost, or would it be best to remove them and make the iterator bidirectional-only prior? Cheers, Matt

3 10

[serialization] Custom archive and arrays
by Bjorn Reese 23 Jan '16

23 Jan '16

I am currently adding support of C++ arrays to a custom oarchive. My archive inherits from boost::archive::detail::common_oarchive and implements save_override(), which will pass any unknown type to boost::archive::save(). This enables me to implement non-intrusive serialization. When I pass an array to boost::archive::save(), it detects that this is an array and then calls detail::save_array_type. This is where my problem starts, as the function is hardcoded to always store a prefixed array count, which is illegal in the format that my custom archive uses. Would it be possible to lift this restriction? My current workaround is to add an overload for arrays to my custom archive, i.e. template <typename T, std::size_t N> void save_override(const T (&data)[N]);

3 5

[type_traits] Tests for implicit convertibility?
by John Maddock 22 Jan '16

22 Jan '16

Folks, I suspect we may have unintentionally backed ourselves into a corner with is_convertible/is_constructible. While trying to fix https://svn.boost.org/trac/boost/ticket/11922 I found I needed to SFINAE-out some conversion operators when the conversion already exists (as an implicit constructor in the target type). So far so easy, but consider: class Int { public: Int(const int& i) {}; Int(const Int& i) = delete; }; static_assert(is_convertible<int, Int>::value, "Ooops"); Now you would think this would pass right? But it doesn't (at least on GCC and clang), and this is true for both boost:: and std:: type_traits and appears to be an unintended side effect of the way is_convertible is defined, that a valid copy constructor is required on the target type. Of course: is_constructible<Int, int>::value is true, but that also catches explicit constructors. So... have we backed ourselves into a corner or do we still have a way to test for implicit-constructibilty that doesn't also require copy-constructibility on the target type? Thanks, John.

2 2

test matrix messages
by Robert Ramey 22 Jan '16

22 Jan '16

I have a certain number of failures for the tests of the serialization library on the test matrix. If I go to get the messages associated with the failure, I rarely get any helpful information. Here are a couple of common cases: http://www.boost.org/development/tests/develop/developer/output/teeks99-08c… http://www.boost.org/development/tests/develop/developer/output/igaztanaga-… Can anything be done about this? Robert Ramey

1 0

[gsoc16] Attn: We need 2016 mentors and project ideas for Boost!
by Niall Douglas 21 Jan '16

21 Jan '16

Dear Boost community, We are now within one month of the beginning of Google Summer of Code 2016! Last year's GSoC was a particularly momentus one as we witnessed the approval by the community for Boost.Hana to enter Boost - congratulations to Louis and his mentor Joel for bringing to Boost a very exciting new C++ library which pushes C++ compilers to their limits. We have also seen greatly improved retention of GSoC students in the community thanks to the improved student selection procedures introduced last year, and the fresh blood brought into Boost has been very evident on the mailing list this year. As part of filling in our application for 2016, we must supply to Google a list of potential GSoC mentors and potential GSoC projects for summer 2016 in order to be approved as an organisation this year. Therefore a lengthy page of awesome project ideas at https://svn.boost.org/trac/boost/wiki/SoC2016 before *February 8th* would be an enormous help to getting us approved again this year and bringing to Boost another US$35,000 of Google funding. If you think yourself able to mentor a student doing some work on Boost this summer, *please* consider adding a description of the proposed work item and your name to the list. Last year we had more slots awarded to us by Google than we had good combinations of student and mentor, so we had to return slots which I believe has not happened here at Boost GSoC in at least a decade. That means that your project ideas have a better chance than ever of receiving funding if you can find a good student, and that is best done by getting project ideas floated *early*. If you want to know more about mentoring a Google Summer of Code funded student work before you nominate yourself, please feel free to ask on the main Boost developers mailing list boost(a)lists.boost.org or via gsoc-admin(a)boost.org. Thank you in advance for your time. --- Boost C++ Libraries Google Summer of Code 2016 admin https://svn.boost.org/trac/boost/wiki/SoC2016

3 2

please add safe numerics to the review queue
by Robert Ramey 21 Jan '16

21 Jan '16

Any chance I could get safe numerics added to the Boost Review queue? THe link to the incubator is here: http://rrsd.com/blincubator.com/bi_library/safe-numerics/?gform_post_id=426 documention here: http://htmlpreview.github.io/?https://github.com/robertramey/safe_numerics/… and github repo here: https://github.com/robertramey/safe_numerics Robert Ramey

1 0

[gsoc16] Can I quickly check if the below really is the best approach?
by Niall Douglas 19 Jan '16

19 Jan '16

Dear Boost, In the prototype https://svn.boost.org/trac/boost/wiki/SoC2016 at https://goo.gl/1CQAuQ I claim "Even with all of Boost's facilities [1] and using C++ 14, this program represents the currently best available method of implementing a static constant associative map of keys to values" and you can find either the code at the link or pasted below. Can I quickly check here if that claim is true? Is there a better way than my example program? BTW by static constant associative map of keys to values I mean the thing me and Tony van Eerd were speaking about here last year and the year before, and indeed frequently at BlackBerry! Niall [1]: I believe Boost.Hana could implement a static constan associative map quite easily, but I'd be fairly sure Hana will likely be beyond most students. --- cut --- #include <initializer_list> #include <experimental/string_view> #include <map> #include <unordered_map> #include <iostream> using std::experimental::string_view; enum class weekday { sunday, monday, tuesday, wednesday, thursday, friday, saturday }; // initializer_list, pair and string_view are constexpr, so this list can be constexpr // (i.e. lives in the mind of the compiler only and has zero representation in generated code) #define STRING_VIEW(str) { str, sizeof(str)-1 } constexpr std::initializer_list<std::pair<const string_view, weekday>> string_to_weekday { { STRING_VIEW("sunday"), weekday::sunday }, { STRING_VIEW("monday"), weekday::monday }, { STRING_VIEW("tuesday"), weekday::tuesday }, { STRING_VIEW("wednesday"), weekday::wednesday }, { STRING_VIEW("thursday"), weekday::thursday }, { STRING_VIEW("friday"), weekday::friday }, { STRING_VIEW("saturday"), weekday::saturday } }; int main(void) { { // Calls malloc() at least 7 times static const std::map<string_view, weekday> to_weekday1 = string_to_weekday; std::cout << "'monday' maps to " << static_cast<int>(to_weekday1.at("monday")) << std::endl; std::cout << "'friday' maps to " << static_cast<int>(to_weekday1.at("friday")) << std::endl; // Calls free() at least 7 times } { // Calls malloc() at least 8 times static const std::unordered_map<string_view, weekday> to_weekday2 = string_to_weekday; std::cout << "'monday' maps to " << static_cast<int>(to_weekday2.at("monday")) << std::endl; std::cout << "'friday' maps to " << static_cast<int>(to_weekday2.at("friday")) << std::endl; // Calls free() at least 8 times } return 0; } -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

13 28

whatever happened to the constrained value library?
by Robert Ramey 18 Jan '16

18 Jan '16

I just stumbled upon the following announcement. http://lists.boost.org/boost-announce/2010/09/0265.php But I don't see any such library as part of boost. What's up with this? Robert Ramey

3 3

Re: [boost] [interprocess] boost::hash - different values for the same input?
by Daniel James 17 Jan '16

17 Jan '16

I altered the subject to include interprocess, since this is relevant there. On 9 December 2015 at 20:13, trafdev <trafdev(a)mail.ru> wrote: > > As per hash_range docs > (http://www.boost.org/doc/libs/1_59_0/doc/html/hash/reference.html#boost.has…) > > "This hash function is not intended for general use, and isn't guaranteed to > be equal during separate runs of a program - so please don't use it for any > persistent storage or communication." > > As per code > (http://www.boost.org/doc/libs/1_59_0/boost/functional/hash/hash.hpp) it > uses hash_combine_impl which doesn't use any random, process_id etc values > which might change during new process launches. > > At the same time, in an example describing container usage in the shared > memory > (http://www.boost.org/doc/libs/1_59_0/doc/html/interprocess/allocators_conta…) > boost::hash is being used: > > typedef boost::unordered_map > < KeyType , MappedType > , boost::hash<KeyType> ,std::equal_to<KeyType> > , ShmemAllocator> > MyHashMap; > > My question is: is it safe to use boost::hash in a shared (persistent) > storage or it's safe only for a particular (non-pointer) types? > > In this case, boost::hash docs should be changed to mention this exceptions, > because otherwise no one could use boost::hash in a shared memory > containers. Sorry about the very slow reply. I'm afraid the answer is that it depends. The reason why I originally wrote that note was because it can generate different hash values when compiled for different platforms or architectures, e.g. a 32-bit executable might generate a different hash value to a 64-bit executable. Also, I occasionally change the algorithm in new versions of boost (and probably will in the next version). For interprocess this currently won't be an issue if all the processes are using the same executable, or using executables built with same version of boost and the same architecture, but could be a problem if that isn't the case. So maybe the Interprocess documentation needs to explain this. But there's another problem coming up. The last proposal I saw for a standard generic hash function will support randomized hash functions (such as siphash) which will only work with interprocess if they are somehow seeded identically. I'll want to support whatever is accepted to the standard (although maybe as a separate library). I'll need to catch up with how that is progressing, as I haven't kept up to date.

5 13

Any-Range containing transformed range fails when compiled with optimizations
by Auer, Jens 17 Jan '16

17 Jan '16

Hi, I have a program which produces different results based on the compiler options. The program uses a boost::any_range containing a transformed range where the transformation function just returns a new object of a simple struct: #include <vector> #include <boost/range.hpp> #include <boost/range/any_range.hpp> #include <boost/range/adaptor/transformed.hpp> #include <iostream> template<typename T1, typename T2> void ASSERT_EQ(T1 x,T2 y) {assert(x == y);}; struct SourceEvent { std::uint32_t event; void* ptr; }; int main() { using boost::adaptors::transformed; using R = boost::any_range<SourceEvent, boost::forward_traversal_tag, SourceEvent, std::ptrdiff_t>; std::vector<std::int32_t> v(100); R r = v | transformed( [](auto const&) {return SourceEvent{0u, nullptr};} ); auto t = v | transformed( [](auto const&) {return SourceEvent{0u, nullptr};} ); ASSERT_EQ( 100u, boost::size(r) ); ASSERT_EQ( 100u, boost::size(t) ); for (auto const& i: t) { ASSERT_EQ(0u, i.event ); ASSERT_EQ(nullptr, i.ptr); } for (auto const& i: r) { ASSERT_EQ(0u, i.event ); ASSERT_EQ(nullptr, i.ptr); } std::cout << "OK" << std::endl; return 0; } When compiled without optimization, it just prints ok. The same source compiled with optimizations asserts, and prints some interesting warnings: In file included from /usr/local/boost-1.60.0/include/boost/range/detail/any_iterator.hpp:22:0, from /usr/local/boost-1.60.0/include/boost/range/any_range.hpp:17, from prog.cc:3: /usr/local/boost-1.60.0/include/boost/range/detail/any_iterator_wrapper.hpp: In member function 'boost::range_detail::any_forward_iterator_wrapper<WrappedIterator, Reference, Buffer>::reference boost::range_detail::any_forward_iterator_wrapper<WrappedIterator, Reference, Buffer>::dereference() const [with WrappedIterator = boost::iterators::transform_iterator<boost::range_detail::default_constructible_unary_fn_wrapper<main()::<lambda(const auto:1&)>, SourceEvent>, __gnu_cxx::__normal_iterator<int*, std::vector<int> >, boost::iterators::use_default, boost::iterators::use_default>; Reference = SourceEvent; Buffer = boost::any_iterator_buffer<64ul>; boost::range_detail::any_forward_iterator_wrapper<WrappedIterator, Reference, Buffer>::reference = SourceEvent&]': /usr/local/boost-1.60.0/include/boost/range/detail/any_iterator_wrapper.hpp:302:57: warning: function may return address of local variable [-Wreturn-local-addr] return dereference_cast<reference>(*m_it); ^ /usr/local/boost-1.60.0/include/boost/range/detail/any_iterator_wrapper.hpp:302:52: note: declared here return dereference_cast<reference>(*m_it); ^ prog.exe: prog.cc:7: void ASSERT_EQ(T1, T2) [with T1 = unsigned int; T2 = unsigned int]: Assertion `x == y' failed. Aborted The example is compiled with gcc 5.2 and boost 1.60 (http://melpon.org/wandbox/permlink/QF1qyw5bWHKwyKJ8) Is there an error in my code? I would guess that transforming a range into a range of new objects of another type is quite common, so it should work. I am also curious why the warning is only emitted when compiling with optimizations. Best wishes, Jens -- Jens Auer | CGI | Software-Engineer CGI (Germany) GmbH & Co. KG Rheinstraße 95 | 64295 Darmstadt | Germany T: +49 6151 36860 154 jens.auer(a)cgi.com<mailto:jens.auer@cgi.com> Unsere Pflichtangaben gemäß § 35a GmbHG / §§ 161, 125a HGB finden Sie unter de.cgi.com/pflichtangaben<http://de.cgi.com/pflichtangaben>. CONFIDENTIALITY NOTICE: Proprietary/Confidential information belonging to CGI Group Inc. and its affiliates may be contained in this message. If you are not a recipient indicated or intended in this message (or responsible for delivery of this message to such person), or you think for any reason that this message may have been addressed to you in error, you may not use or copy or deliver this message to anyone else. In such case, you should destroy this message and are asked to notify the sender by reply e-mail.

3 7

Re: [boost] [gsoc16] Can I quickly check if the below really is the best approach?
by Shangtong Zhang 16 Jan '16

16 Jan '16

Hi, > // At global scope, allocates no memory whatsoever > static const constexpr static_map<int, const char *> map { > { 5, "apple" }, > { 8, "pear" }, > { 0, "banana" }, > ... > }; > // Works, constexpr "apple" > constexpr const char *what_is_5 = map[5]; > // Works > assert(map[5] && !strcmp(map[5], "apple"); > // Works > map[5]="orange"; > assert(map[5] && !strcmp(map[5], "orange"); > // Throws exception as there is no key 6 > map[6]; > map.at <http://map.at/>(6); I have difficulty understanding this, As variable map is const and constexpr, how can map[5]=“orange” work? I don’t know how to implement this, where to store the “orange”. Could anyone help me? Thanks, Shangtong Zhang, Senior Student, School of Computer Science, Fudan University, PRC.

2 1

[gsoc16]Interest in static map
by Shangtong Zhang 15 Jan '16

15 Jan '16

Hi Niall Douglas, I’m interested in the project static map and want to contribute to it in gsoc 2016. And I try to start with the programming competency test. Following is what I have done, https://github.com/ShangtongZhang/StaticMap/blob/master/main.cpp <https://github.com/ShangtongZhang/StaticMap/blob/master/main.cpp> Could you please give me some advice? In addition, I’m a little confused with // This should fail elegantly and usefully ... //constexpr std::array<unsigned, 0> string_hashes_fail = hash_strings(5); My understanding is that it will raise a run-time exception, is it right? Thanks, Shangtong Zhang, Senior Student, School of Computer Science, Fudan University, PRC.

2 1

Is there interest in Computable Calculus?
by Damian Vicino 15 Jan '16

15 Jan '16

Hi, I’m interested in developing basic support of “real numbers” for computable calculus applications. In computable calculus, reals have infinite precision (certain restrictions may apply). The usual approach is representing numbers as functions producing digits. An arithmetic operation produces a new function using the functions in the operands and some simple expression manipulations. When a number needs to be evaluated (e.g., for comparisons where expression rules are unknown), enough digits for reaching an answer are generated using the functions. For example, 3.14 < pi requires generating 3 digits to answer “true”. The algorithms for arithmetic operations and evaluation are well known, and multiple implementations were developed (mostly in the 90s). However, I couldn’t find an open source implementation and had to come up with my own for working in a project during the last 2 years. My preferred reference for the required algorithms is the book: Aberth, Oliver. Computable Calculus. Academic Press, 2001. In particular, my initial scope would be the 4 arithmetic operations (+, -, *, /), and the comparison operators (<, =) for reals. Someone is interested in such a library in boost?

4 4

IS THERE A WAY TO FIND IF A CERTAIN TYPE HAS A CERTAIN MEMBER?
by Juan Dent 15 Jan '16

15 Jan '16

> HI, > > > I have read that via enable_if and other constructs, one can declare a member of a type conditionally. > > What I need is a way to be able to test whether a certain type has a certain method or member data, so that I can call it or use it accordingly. > > Does boost have something like this?? > > > Regards, > Juan

4 3

a safe integer library
by Robert Ramey 14 Jan '16

14 Jan '16

Arithmetic operations in C++ are NOT guaranteed to yield a correct mathematical result. This feature is inherited from the early days of C. The behavior of int, unsigned int and others were designed to map closely to the underlying hardware. Computer hardware implements these types as a fixed number of bits. When the result of arithmetic operations exceeds this number of bits, the result will not be arithmetically correct. I have crafted a library to address this issue once and for all. You can find out more about this by checking out the page for Safe Numerics at the boost library incubator. www.blincubator.com I hereby request that this library be added to the boost review queue. I've also made a proposal for the C++ Standards committee to include a simplified version of this library as part of he C++ standard. You can see the proposal at http://www.rrsd.com/software_development/safe_numerics/proposal.pdf Robert Ramey

14 42

ATTENTION: Library requirements..
by Rene Rivera 13 Jan '16

13 Jan '16

Last Summer I brought up the subject of library organization requirements to make it easier to write the development and release tools needed to keep the Boost machine going. See this thread < http://lists.boost.org/Archives/boost/2015/06/223027.php> for a refresher. This morning I committed the first part of the above.. A new set of library requirements that take into account existing practices. Adds some additional integration requirements. And puts in limits to reduce some integration burdens. Please read the new requirements carefully < http://www.boost.org/development/requirements.html#Requirements>. It would be wonderful if authors start making changes as needed immediately. But at some point I, and possible others, will start making changes to all libraries to follow the requirements. So that the release, build, and testing teams can move forward with better support. And of course, more cleanups and such will follow. Hopefully before the next release is out the door. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

16 80

[BPM] Supporting an alternative to meta/libraries.json
by Louis Dionne 13 Jan '16

13 Jan '16

Dear list, Currently, all Boost libraries are required to have a meta/libraries.json file at their root, which contains some meta-data describing the library. As I understand it, this meta-data is then used to generate the list of all libraries with their description when a release is done. I find having such a directory at the root of every library annoying, since it clutters it. Furthermore, for metaprogramming libraries, the name can be slightly confusing since meta/ might be expected to contain something different. I propose that we allow libraries to specify their metadata in a `.boost` file located at their root. Using a dotfile is the most common way of providing information for an external service (for example .travis.yml), and dotfiles are usually more discrete when viewing the project in an editor. Furthermore, making `boost` part of the filename is more descriptive. I have submitted a pull request to BPM [1] adding the ability to fetch the meta data in a .boost file. The meta-data can still be provided in meta/libraries.json, so this should not affect existing libraries. Related questions that we might want to consider: - Should it be .boost.json instead of .boost? - Perhaps we could store the meta-data for all the libraries in the same place, and get rid of the individual meta-data files? - If this suggestion is accepted, is there more to modify than BPM? Regards, Louis [1]: https://github.com/boostorg/bpm/pull/1

5 19

[test] BOOST_TEST macro and std::max
by Benedek Thaler 13 Jan '16

13 Jan '16

Hi, I'd expect the following cheks to pass: BOOST_TEST(3u == (std::max)(0u, 3u)); BOOST_TEST(3u == ((std::max)(0u, 3u))); But both fails with: check 3u == ((std::max)(0u, 3u)) has failed [3 != 7095312] Did I miss something regarding BOOST_TEST usage? Platform: Linux, GCC 5.3, Boost 1.60 Thanks, Benedek

4 15

Re: [boost] asio config.hpp macro redefinition - mistake?
by Curdeius Curdeius 13 Jan '16

13 Jan '16

> > ---------- Wiadomość przekazana dalej ---------- > From: "John M. Dlugosz" <mpbecey7gu(a)snkmail.com> > To: boost(a)lists.boost.org > Cc: > Date: Tue, 12 Jan 2016 17:32:48 -0600 > Subject: [boost] asio config.hpp macro redefinition - mistake? > In file boost_1_59_0\boost\asio\detail\config.hpp line 227 gives a macro > redefinition warning. > (...) > It seems that this is missing a guard or has the if/else things mixed up. > This was fixed some time ago. See https://github.com/boostorg/asio/commit/b9cb61416e1972d7490d91da91df549703f… . Regards, Marek Kurdej

1 0

[fusion]enabler.hpp junk character at start of file
by Aparna Kumta 13 Jan '16

13 Jan '16

All accumulator tests fail when compiled with Oracle Solaris Studio in 'dev' branch as follows: "../boost/fusion/support/detail/enabler.hpp", line 1: Error: A declaration was expected instead of "???". 1 Error(s) and 1 Warning(s) detected. See http://www.boost.org/development/tests/develop/developer/output/oracle-spar… It appears that in file boost/fusion/support/detail/enabler.hpp, there is some junk character at the start of file. This cannot be observed via vi editor, but with ' head -1 enabler.hpp', this can be seen. % head -1 enabler.hpp ��/*===================================== Perhaps these characters should be removed? When I view the file on github, I do not see the issue, however when I try to edit the file, I see it. Will submit a PR. Thanks, Aparna

2 2

[regression] Regression tests for 'develop' has error
by Edward Diener 13 Jan '16

13 Jan '16

Trying to open the regression test results for 'develop' page gives: "Error extracting file: Error code 3 - A severe error in the zipfile format was detected." This has happened numerous times before. Can this be fixed, not only now but permanently ? Surely there must be some way of determining why the zipfile format has a severe error and preventing this in the future.

5 16

asio config.hpp macro redefinition - mistake?
by John M. Dlugosz 13 Jan '16

13 Jan '16

In file boost_1_59_0\boost\asio\detail\config.hpp line 227 gives a macro redefinition warning. // Compliant C++11 compilers put noexcept specifiers on error_category members. #if !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT) # if (BOOST_VERSION >= 105300) # define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT BOOST_NOEXCEPT # elif defined(__clang__) # if __has_feature(__cxx_noexcept__) # define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true) # endif // __has_feature(__cxx_noexcept__) # elif defined(__GNUC__) # if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4) # if defined(__GXX_EXPERIMENTAL_CXX0X__) # define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true) # endif // defined(__GXX_EXPERIMENTAL_CXX0X__) # endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4) # endif // defined(__GNUC__) # if defined(BOOST_ASIO_MSVC) # if (_MSC_VER >= 1900) # define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true) // ****** here ****** # endif // (_MSC_VER >= 1900) # endif // defined(BOOST_ASIO_MSVC) # if !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT) # define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT # endif // !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT) #endif // !defined(BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT) To paraphrase, the block reads # if (BOOST_VERSION >= 105300) // it is: 105900 >= 105300 *# define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT BOOST_NOEXCEPT* ⋮ # if defined(BOOST_ASIO_MSVC) # if (_MSC_VER >= 1900) *# define BOOST_ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)* # endif // (_MSC_VER >= 1900) # endif // defined(BOOST_ASIO_MSVC) It seems that this is missing a guard or has the if/else things mixed up.

2 1

[property_tree] Still being maintained?
by Gavin McNiff 12 Jan '16

12 Jan '16

Hi, I was wondering if the Property_Tree library is still being actively maintained. There are 9 GitHub pull requests stacked up since the summer? Best regards Gavin McNiff

2 2

[err] RFC
by Domagoj Saric 11 Jan '16

11 Jan '16

https://github.com/psiha/err README.md copy-paste: --------------------------------------------- err - yet another take on C++ error handling. We have throw and std::error_code, what more could one possibly want? --------------------------------------------- std::error_code&co tried to solve or at least alleviate the problem of overhead of using exceptions (in terms of both source code verbosity and binary code size&speed) with functions which need to report failures that need not be 'exceptional' depending on the context of the call (thereby requiring try-catch blocks that convert exceptions to 'result codes'). Unfortunately, the way it was finally implemented, std::error_code did not quite accomplish what it set out to do: • in terms of runtime efficiency: 'manual'/explicit EH (try-catch blocks) is no longer needed but the compiler still has to insert hidden EH as it has to treat the functions in question as still possibly throwing (in fact the implementation/codegen of functions which use std::error_code for error reporting becomes even fatter because it has to contain both return-on-error paths and handle exceptions) • in terms of source code verbosity: again, try-catch blocks are gone but separate error_code objects have to be declared and passed to the desired function. Enter boost::err: 'result objects' (as opposed to just result or error codes) which can be examined and branched upon (like with traditional result codes) or left unexamined to self-throw if they contain a failure result (i.e. unlike traditional result codes, they cannot be accidentally ignored). Thanks to latest C++ language features (such as r-value member function overloads) incorrect usage (that could otherwise for example lead to a result object destructor throwing during a stack-unwind) can be disallowed/detected at compile time. Discussions where the concept (or a similar one) was first concieved of and/or so far discussed: • http://boost.2283326.n4.nabble.com/system-filesystem-v3-Question-about-erro… • http://cpptips.com/fallible • https://github.com/ptal/std-expected-proposal • https://github.com/ptal/expected • https://github.com/adityaramesh/ccbase/blob/master/include/ccbase/error/exp… • http://stackoverflow.com/questions/14923346/how-would-you-use-alexandrescus… • https://svn.boost.org/trac/boost/wiki/BestPracticeHandbook#a8.DESIGN:Strong… • http://2013.cppnow.org/session/non-allocating-stdfuturepromise **************************************************************** For starter's, to reduce the length of the first post, I'll assume that everyone as at least somewhat familiar with similar/related proposals from Andrei Alexandrescu (std::expected) and Niall Douglas (std::monad) to which I gave links above. What, primarily, makes (Boost.)Err different from other proposals is the ability to (using latest C++ features) detect/distinguish between temporaries and 'saved' return values by using two different class templates (result wrappers), fallible_result (for rvalues) and result_or_error (for lvalues) and thus minimise or often completely eliminate any extra verbosity: If we had a function foo() that produces bar_t objects but can fail with an err_t, up till now we had two options: * bar_t foo() throw( err_t ); * optional<bar_t> foo( err_t & ); Err enables the library writer to write a single API and a single implementation: err::fallible_result<bar_t, err_t> foo(); where fallible_result is the class template that wraps temporaries/rvalues returned from functions and its member functions are all declared with && (i.e. callable only on rvalues) so you get a compiler error if you save it to an auto value and try to do anything with it. The two exceptions are the implicit conversion operators to: - bar_t, which will either return bar_t or throw err_t and which is used for the 'EH code path' bar_t my_bar( foo() ); - err::result_or_error<bar_t, err_t> which is used for the 'oldsk00l nothrow error code path' err::result_or_error<bar_t, err_t> maybe_bar( foo ); if ( maybe_bar ) { print( *maybe_bar ); } else { log( maybe_bar.error() ); } Also, if the fallible_result rvalue is left uninspected and contains an error its destructor will throw (which AFAICT should be safe considering it is an rvalue and no other exception can possibly be active at the same time) - this makes code that uses Err enabled libraries/APIs but relies on EH almost indistinguishable from 'classic EH' APIs (almost because the one difference that remains is with the immediate use of the return value: because of the wrapper class one can no longer write foo().do_something() but has to implicitly use the -> operator and write foo()->do_something() where the -> operator will check-and-throw if foo() did not succeed). To wrap up, this approach gives the user the immediate and fine grained control over which error handling mechanism he/she wants to use while allowing the developer to write a single API and implementation - AFAICT it is a no brainer replacement for <system_error>, it is less verbose and much more efficient ;-) ps. the small library @ https://github.com/psiha/err is by no means a finished product, it contains no tests or documentation but 'it works' (i.e. it is used in the, also upcoming, https://github.com/psiha/mmap)...I'm bringing it to public view for scrutiny, discussion and guidance lest I steer in the wrong direction ;) -- "What Huxley teaches is that in the age of advanced technology, spiritual devastation is more likely to come from an enemy with a smiling face than from one whose countenance exudes suspicion and hate." Neil Postman

4 20

Add Boost.Convert to the Trac
by Vicente J. Botet Escriba 11 Jan '16

11 Jan '16

Hi, I have requested this (https://svn.boost.org/trac/boost/ticket/11814) 6 weeks ago without response. Is anyone maintaining the Trac component? I see Doug Gregor, but I believe he is not actively working on Boost. Best, Vicente

2 2

[trac] boost 1.61
by Raffi Enficiaud 11 Jan '16

11 Jan '16

Hi all, Would it be possible to add 1.61 to the roadmap? Thanks, Raffi

2 1

want to contribute in boost c++ organisation
by Aman Varshney 11 Jan '16

11 Jan '16

As I am a 2nd year computer Science student at IIIT-Hyderabad. Being a beginner I have some idea about C++ and want to start contributing to open source. I found the boost c++library. It would be great if I get some directions from you as to where to start from. Thank You

1 0

[regression] Summary for develop is unavailable
by Antony Polukhin 08 Jan '16

08 Jan '16

Hi, At http://www.boost.org/development/tests/develop/developer/summary.html you'll find "Error extracting file: Error code 3 - A severe error in the zipfile format was detected." Please, could someone fix that? -- Best regards, Antony Polukhin

1 1

Ynt: Building Boost (1.60) with Clang and NDK
by Fatih Kıralioğlu 07 Jan '16

07 Jan '16

Ok, I am sharing my build.bat user-config-android.jam file below, from the outputs, clang is using mingw headers, for clang build, is mingw headers really necessary? build.bat: set CXXFLAGS="-I%ANDROID_NDK%/platforms/android-9/arch-arm/usr/include -I%ANDROID_NDK%/sources/cxx-stl/gnu-libstdc++/4.9/include -I%ANDROID_NDK%/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi/include" set TOOLSET=gcc-android b2 --toolset=%TOOLSET% --user-config=./user-config-android.jam cxxflags=%CXXFLAGS% threadapi=pthread --prefix=..\boost_android_arm --builddir=./ target-os=linux --with-date_time --with-filesystem --with-regex --with-log define=BOOST_FILESYSTEM_VERSION=3 --with-program_options --with-signals --with-system --with-thread link=static runtime-link=shared threading=multi install user-config-android.jam: androidNDKRoot = android-ndk-r10e ; # put the relevant path using clang : android : $(androidNDKRoot)/toolchains/llvm-3.6/prebuilt/windows-x86_64/bin/clang++ : <compileflags>--sysroot=$(androidNDKRoot)/platforms/android-21/arch-arm <compileflags>-Os <compileflags>-fno-strict-aliasing <compileflags>-O2 <compileflags>-DNDEBUG <compileflags>-g <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/gnu-libstdc++/4.9/include <compileflags>-I$(androidNDKRoot)/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi/include <compileflags>-D__GLIBC__ <compileflags>-D__ANDROID__ <compileflags>-D_GLIBCXX__PTHREADS <compileflags>-D__arm__ <compileflags>-D_REENTRANT And I'am getting this error: g++: error: unrecognized command line option '-stdlib=libc++' clang++.exe: error: linker (via gcc) command failed with exit code 1 (use -v to see invocation) "android-ndk-r10e/toolchains/llvm-3.6/prebuilt/windows-x86_64/bin/clang++" -o "bin.v2\libs\date_time\build\clang-linux-andr oid\release\target-os-android\threadapi-pthread\threading-multi\libboost_date_time-clang-mt-1_60.so.1.60.0" -Wl,-soname -Wl,libboost_date_time-clang-m t-1_60.so.1.60.0 -shared -Wl,--start-group "bin.v2\libs\date_time\build\clang-linux-android\release\target-os-android\threadapi-pthread\threading-mult i\gregorian\greg_month.o" "bin.v2\libs\date_time\build\clang-linux-android\release\target-os-android\threadapi-pthread\threading-multi\gregorian\greg_ weekday.o" "bin.v2\libs\date_time\build\clang-linux-android\release\target-os-android\threadapi-pthread\threading-multi\gregorian\date_generators.o" -Wl,-Bstatic -Wl,-Bdynamic -Wl,--end-group -stdlib=libc++ -lc++_shared -Landroid-ndk-r10e/sources/cxx-stl/llvm-libc++/libs/ar meabi ...failed clang-linux.link.dll bin.v2\libs\date_time\build\clang-linux-android\release\target-os-android\threadapi-pthread\threading-multi\libboost_da te_time-clang-mt-1_60.so.1.60.0... ...skipped <p..\boost_android_arm\lib>libboost_date_time-clang-mt-1_60.so.1.60.0 for lack of <pbin.v2\libs\date_time\build\clang-linux-android\release \target-os-android\threadapi-pthread\threading-multi>libboost_date_time-clang-mt-1_60.so.1.60.0... clang-linux.compile.c++.without-pth bin.v2\libs\system\build\clang-linux-android\release\target-os-android\threadapi-pthread\threading-multi\error_cod e.o In file included from libs\system\src\error_code.cpp:16: In file included from .\boost/system/error_code.hpp:19: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/include\ostream:38: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/include\ios:42: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/include\bits/ios_base.h:39: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/include\ext/atomicity.h:35: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi/include\bits/gthr.h:148: In file included from android-ndk-r10e/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi/include\bits/gthr-default.h:48: android-ndk-r10e/platforms/android-21/arch-arm/usr/include\pthread.h:164:58: error: unknown type name 'clockid_t'; did you mean ' clock_t'? int pthread_condattr_getclock(const pthread_condattr_t*, clockid_t*) __nonnull((1, 2)); ^ c:/mingw/include\time.h:71:14: note: 'clock_t' declared here typedef long clock_t; Fatih KIRALİOĞLU R&D Engineer fatih.kiralioglu(a)sestek.com www.sestek.com ________________________________________ Gönderen: Fatih Kıralioğlu Gönderildi: 6 Ocak 2016 Çarşamba 21:13 Kime: boost(a)lists.boost.org Konu: Ynt: [boost] Building Boost (1.60) with Clang and NDK Thanks for the responses, The last error I got is: "In file included from libs\date_time\src\gregorian\greg_weekday.cpp:16: In file included from libs\date_time\src\gregorian/greg_names.hpp:14: In file included from .\boost/date_time/gregorian/greg_month.hpp:14: In file included from .\boost/shared_ptr.hpp:17: In file included from .\boost/smart_ptr/shared_ptr.hpp:35: In file included from .\boost/smart_ptr/detail/spinlock_pool.hpp:25: In file included from .\boost/smart_ptr/detail/spinlock.hpp:47: In file included from .\boost/smart_ptr/detail/spinlock_gcc_arm.hpp:12: In file included from .\boost/smart_ptr/detail/yield_k.hpp:28: In file included from .\boost/predef.h:20: In file included from .\boost/predef/hardware.h:14: .\boost/predef/hardware/simd.h:77:5: error: "Multiple SIMD architectures detecte d, this cannot happen!" # error "Multiple SIMD architectures detected, this cannot happen!" " I have also installed and set it as an include dir for b2.exe to use clang and i got the error above fatih ________________________________________ Gönderen: Boost <boost-bounces(a)lists.boost.org> adına Ben Pope <benpope81(a)gmail.com> Gönderildi: 6 Ocak 2016 Çarşamba 19:06 Kime: boost(a)lists.boost.org Konu: Re: [boost] Building Boost (1.60) with Clang and NDK On Wednesday, January 06, 2016 04:06 AM, Fatih Kıralioğlu wrote: > Has anyone built the Boost with Clang and NDK other than CryStax? If so, can you post the related config.jam and build script? I have handled gcc build but clang is very very chalnllenging and no one including the guys in Stackoverflow could answer it. I haven't noticed any problems building boost for Android with the NDK, I honestly have no idea why I see so many people asking how to do it, or patch sets or whatever. I'm using gcc-4.9 and std=c++14 on linux x64 targeting armv7. I package the toolset I want (android 15, gcc-4.9) and pass that sysroot in the CXXFLAGS, I tend not to interfere with the build system of boost or android very much, preferring to drive everything from cmake (for my own projects). What problems have you seen? The NDK is moving entirely to clang, the next release will see gcc deprecated, so I'll have to have a play with moving over to clang, but in my experience, everything I do works equally well on clang for armv7, armv8 and x64. The only problem I remember having is thread locals on iOS targets, but my memory is short, and it only takes a few lines of code to emulate that for most purposes. If you explain what problems you've seen, which libraries, toolsets and command lines, perhaps you'll trigger a memory of a problem I've solved. I can give you more details of my configuration on the weekend, if required. As a sidenote, I'm hoping to bring up a boost/clang/linux/armv8 build bot if and when my Pine64 arrives and I get Ubuntu/Debian running on it (by April if all goes well). I have no idea how quickly it will cycle though, my current x64 tests take around 16 hours for gcc-4.9, gcc-5.2 and clang-3.7, I'll probably have to drop gcc-4.9. I had to give up on my regular sanitizer builds on x64 as they just take too long and there seemed to be very little interest. Unfortunately I don't have dedicated machines to run the tests. Ben _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

2 1

[review][qvm] QVM formal review report
by Adam Wulkiewicz 07 Jan '16

07 Jan '16

Dear Boost community, The review period for Emil Dotchevski's QVM library has concluded. I'd like to thank everyone who participated in the discussions, esspecially those who sent formal reviews. Only four votes were casted: - 1 vote for acceptance * Rajaditya Mukherjee - 2 votes for conditional acceptance * Rainer Deyke * Oswin Krause - 1 vote for rejection * Phil Endecott However more people commented on issues on the mailing list. Comments received during the course of the review were generally positive, with a number of technical issues identified that need to be addressed. The review identified no fundamental problems in the design or implementation of the library that would entail rejection. The final version of the library can be fully accepted once Emil has addressed the issues identified during the review. Therefore I'm happy to say: Emil Dotchevski's Boost.QVM library is CONDITIONALLY ACCEPTED. Below is a summary of technical concerns: - The identifiers should be made more verbose. This is true both for function names as well as identifers containing "q"/"v"/"m" parts. The former should be replaced with full words, e.g. "transp" -> "transpose". The latter should be replaced at least with "qua"/"quat"/"vec"/"mat" respectively, so e.g. "v_traits" -> "vector_traits"/"vec_traits", "col_m" -> "col_mat", etc. - Many participants found the swizzling syntax using comma operator confusing or not good enough. There were many suggestions about the possible replacements: * v%XY - the old operator% syntax * (v,XY) - the comma operator syntax currently used by QVM * (v,asXY) - in order to limit potential conflicts with macros * XY(v) - function syntax, MOST PREFERED * v.XY() - probably the best but currently not possible (n4165, n4174) * ref(v).XY() * ref(v)[xy] * swizzle(v, xy) * ref(v)->xy The function syntax, i.e. XY(v), was the most prefered solution. Some of the participants appreciated the comma operator as well because of the similarity with shader languages syntax. The library could provide a few alternatives that could be picked by the user, e.g. both a comma and function syntax. - There were concerns regarding deduce_xx set of traits, in particular that traits taking two arguments (deduce_q2, deduce_v2 and deduce_m2) can cause ODR issues in a case when e.g. third-party libraries depending on QVM specialized these traits differently and those libraries were used together. There were no consensus if this is indeed a library issue or how this issue could be handled in general. Taking into account that the specialization of these traits is optional it'd be sufficient to describe the issue in the documentation and discourage the users from specializing those traits for types defined outside of their own code. - There was also a suggestion to use the same names that are already being used in other well-known libraries to make the interface more intuitive, e.g. mag() could be replaced by norm() (used in Eigen and Armadillo libraries), mag2() could be replaced by norm_squared() or norm_sqr(), etc. This would also make the latter more verbose. I'd let the decission how to deal with it to Emil. - Another suggestion was to replace read/write semantics with get/set semantics or at least to make the r/w/ir/iw identifiers more verbose. Here, I'd let the decission how to deal with it to Emil as well. - Aside from the issues described above, there were also suggestions that the scope of QVM library could/should be broadened to include functionalities from domains other than computer graphics, e.g. linear algebra, geometry, physics, robotics, etc. Oswin Krause requested that an consensus on the scope of the library should be made before the acceptance of the library. Phil Endecott expressed that the library is too small to be a standalone library. However as a Boost.Geometry developer I may say that the scopes, design rationales, internal structures, etc. of both libraries are different. AFAIK it's also true for Boost.Polygon. Furthermore, if my understanding is correct after reading various discussions the community finds the library useful even in the current state, some of the participants already used the library in their projects. Furthermore I'm sure that future users of QVM will suggest additions to the QVM library if they think it's necessary, so the scope will be broadened in a natural way. Though of course I encourage Emil to start a discussion with the community regarding this issue. - Regarding the documentation, various people suggested the following improvements: * it should start with a "Quick Start" page showing how to use the QVM built-in types to do some high-school linear algebra, * make it more obvious which functions are classified as "operations" and which are "view proxies", * contain more examples of every function as well as some bigger real-life examples. Please let me know if you think something is wrong. Regards, Adam

3 4

Building Boost (1.60) with Clang and NDK
by Fatih Kıralioğlu 06 Jan '16

06 Jan '16

Has anyone built the Boost with Clang and NDK other than CryStax? If so, can you post the related config.jam and build script? I have handled gcc build but clang is very very chalnllenging and no one including the guys in Stackoverflow could answer it. Many Thanks. Fatih

4 3

[multiprecision] Creation from a range
by Fernando Pelliccioni 06 Jan '16

06 Jan '16

Hi John, hi all, Is there any way to create an Integer (or a number) from a range (bounded or counted)?; or from a string_view (string_ref)? Roughly speaking, something like: XintXXX_t make_from_bounded_range(I f, I l); XintXXX_t make_from_counted_range(I f, size_t n); If not exist, I can make a contribution, are you interested? Thank you very much and best regards, Fernando Pelliccioni.

3 3

[gsoc16] Re: Potential contribution scenarios?
by Miguel Coimbra 06 Jan '16

06 Jan '16

> It is not hard to find either myself or Antony. Both of us are here, > and both of us are at the top of Google search results for our names. Probably my bad, I only bumped into LinkedIn references. I'll wait for a reply from Antony as well, thanks. I will explore other ideas as well. > 1. A thing Boost really could do with is a decent (optionally > mmappable) dense hash map implementation, so the hash map could > contain billions of items and mostly reside on disk yet lookups would > still be very fast. I have some questions regarding this first idea. I believe a concept and implementation already exist and are actually in use at Google: http://goog-sparsehash.sourceforge.net/doc/dense_hash_map.html Quoting from that page: ** dense_hash_map is distinguished from other hash-map implementations by its speed and by the ability to save and restore contents to disk. On the other hand, this hash-map implementation can use significantly more space than other hash-map implementations, and it also has requirements -- for instance, for a distinguished "empty key" -- that may not be easy for all applications to satisfy. This class is appropriate for applications that need speedy access to relatively small "dictionaries" stored in memory, and for applications that need these dictionaries to be persistent." ** So what you want is something like this, but able to "contain billions of items and mostly reside on disk yet lookups would still be very fast"? I assume the "billions of items" is what is lacking from that dense_hash_map already in use by Google? Is this the difference between that and your idea? Assuming this is indeed what you were proposing, would the work encompass defining an API and also exploring mmap for lazy iteration for performance gains in the context of handling billions of items? Kind regards, Miguel E. Coimbra

2 1

Hi! Want to Contribute
by shubham tibra 06 Jan '16

06 Jan '16

Hello everone, I am Shubham Tibra, a student of IIT KHARAGPUR, INDIA and new to open source community. I can code in C, C++ and I would like to contribute in Boost C++ Libraries. Can someone help me in getting started? Thanks in advance.

2 1

Regarding Contribution to boost C++ Libraries
by Kanika Midha 06 Jan '16

06 Jan '16

Hello All, I am a third year undergraduate student. I am new to open source and I want to participate in GSOC with Boost C++ Libraries. Can anyone guide me on how to move forward with this. Thanking You, With Best Regards, Kanika Midha

2 1

C++Now 2106 Call for Submission
by Jon Kalb 06 Jan '16

06 Jan '16

Boost Developers, The Call for Submissions for C++Now 2016 (AKA BoostCon) has been released: http://cppnow.org/2016-conference/announcements/2015/11/17/call-for-submissi on.html The deadline for submitting is very near and cannot be extended, so don¹t delay your submission. The conference will be held in Aspen the week of May 9th. See you in Aspen! Jon

4 3

[Locale] MSVC 2015 facets issue
by Artyom Beilis 04 Jan '16

04 Jan '16

Hello, Today I had a discussion on this ticket https://svn.boost.org/trac/boost/ticket/11878 There was a basic issue with Boost.Locale that couldn't format numbers at all properly, after back and forth it was discovered an issue with MSVC library. https://svn.boost.org/trac/boost/ticket/11878#comment:10 What is the best way to address this issue (open a bug there is no github issue tracker on this :-) ... Thank You, Artyom Beilis

3 3

GSoC project Concurrent Hash Tables
by Shangtong Zhang 04 Jan '16

04 Jan '16

Hi Niall Douglas, I’m a senior student and want to take part in GSoC 2016. I’m interested in the project Concurrent Hash Tables in GSoC 2015 ideas, is it still available in GSoC 2016? I just found some links are invalid in the project description https://svn.boost.org/trac/boost/wiki/SoC2015 <https://svn.boost.org/trac/boost/wiki/SoC2015> Thanks, Shangtong Zhang, Senior Student, School of Computer Science, Fudan University, PRC.

2 1

Problems building Boost libraries for Windows Store when C++/CX is involved
by Mikael Olenfalk 04 Jan '16

04 Jan '16

Hi, I am working on porting the boost libraries we depend on to winrt, most porting is rather straightforward (basically switch from win32 apis which are 20 years old to apis which are 15 years old :D ). However I have hit a bit of a problem when compiling Boost.Log. Boost.Log depends on Boost.Asio which uses C++/CX to call some of the newer Store APIs (Windows::Networking and friends). When I build I get these errors: compile-c-c++ ..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj dump_ssse3.cpp ..\..\..\libs\log\src\dump_ssse3.cpp: fatal error C1107: could not find assembly 'platform.winmd': please specify the assembly search path using /AI or by setting the LIBPATH environment variable call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" x86 store >nul cl /Zm800 /ZW /EHsc -nologo @"..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj.rsp" (As you can see I have monkey-patched msvc.jam to append the "store" argument to vcvarsall.bat - to no avail :( -- the monkey-patch is here if you want to look at it: https://github.com/mauve/build/commits/universal-windows-boost-1.59.0 ) The @response file looks like this: "..\..\..\libs\log\src\dump_ssse3.cpp" -Fo"..\..\..\bin.v2\libs\log\build\msvc-14.0\debug\log-api-winnt\threading-multi\windows-api-store\dump_ssse3.obj" -TP /Z7 /Od /Ob0 /W3 /GR /MDd /Zc:forScope /Zc:wchar_t /wd4675 /EHs /arch:SSE2 /bigobj /wd4003 /wd4456 /wd4459 /wd4503 -c -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_DATE_TIME_DYN_LINK=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_LOG_BUILDING_THE_LIB=1 -DBOOST_LOG_DLL -DBOOST_SPIRIT_USE_PHOENIX_V3=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_DONT_USE_CHRONO=1 -DBOOST_THREAD_USE_DLL=1 -DDATE_TIME_INLINE -DWINAPI_FAMILY=WINAPI_FAMILY_APP -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_WIN32_WINNT=0x0603 "-I..\..\.." Regards, Mikael

4 10

Generic type inferencer function?
by Nat Goodspeed 04 Jan '16

04 Jan '16

Our code has any number of instances of this pattern: template <typename T, typename U> class SomeTemplate { SomeTemplate(const T& t, const U& u); ... }; template <typename T, typename U> SomeTemplate<T, U> make_SomeTemplate(const T& t, const U& u) { return SomeTemplate<T, U>(t, u); } Am I overlooking a generic boost::make<something>() of this general form? template <template<typename...> class CLASS_TEMPLATE, typename... ARGS> CLASS_TEMPLATE<ARGS...> make(ARGS && ... args) { return CLASS_TEMPLATE<ARGS...>(std::forward<ARGS>(args)...); } If that doesn't already exist... would it be useful to add (a less naive version) somewhere?

10 18

[multiprecision] uses boost::math::gcd without including the header
by Peter Dimov 04 Jan '16

04 Jan '16

include/boost/multiprecision/cpp_int/misc.hpp uses boost::math::gcd (and lcm), but does not include common_factor_rt.hpp.

2 2

Potential contribution scenarios?
by Miguel Coimbra 04 Jan '16

04 Jan '16

Dear Community, This is my first post, apologies if I am breaking any rule with this. I've wanted to learn and improve my C++ skills for some time now. Learning more about Boost's usage and contributing to it has been on my mind. As a Ph.D student (Instituto Superior Técnico, Portugal), I became aware of Boost's participation in Google's Summer of Code and read up on some of Boost's past projects. Two ideas of GSoC2015 in particular caught my attention: - Concurrent Hash Tables - Mentor: Niall Douglas - Boost Document Library development - Mentor: Antony Polukhin I have been looking for direct contacts to learn about some of these ideas (Niall Douglas and Antony Polukhin, respectively) from 2015's Google Summer of Code to find out more, but was unsuccessful so far. While the first idea was not put into practice, the second one was undertaken (by Anurag Ghosh if I am not mistaken). Would anyone be able to point me in a direction to learn more about the state of work on these two ideas (specially the Document Library) and (if possible) if they are available for me to pick up and look into ways of contributing? Perhaps querying the mentors of those ideas for feedback? Thank you very much for your time, Kind regards, Miguel E. Coimbra

2 1

How to start Contributing !
by Yuvraj Singh 03 Jan '16

03 Jan '16

I am new to boost C++ libraries. I want to contribute to org and Participate in GSOC'2016 can someone please guide me through it. I have looked through the page https://svn.boost.org/trac/boost/wiki/SoC2016 . Can someone please help me about *C++ programming aptitude test *mentioned on the page. How and when it is organised and what type of questions are asked ?. *Thanks !*

2 1

Status of the CMake-ification
by Louis Dionne 02 Jan '16

02 Jan '16

Dear Boost, I'd like to inquire about the status of the CMake-ification of Boost that had been started a while ago. AFAICT, the effort is completely stopped now; is this correct? Also, I'd like to poll the community to gauge interest in the rebirth of such an effort. __I'm not proposing myself to work on such a rebirth__, but I'm just curious to know what the community thinks about it. I, for one, would love to see it happen. Regards, Louis -- View this message in context: http://boost.2283326.n4.nabble.com/Status-of-the-CMake-ification-tp4681599.… Sent from the Boost - Dev mailing list archive at Nabble.com.

14 25

[winapi] [thread] Conflicting declarations on MinGW
by Antony Polukhin 01 Jan '16

01 Jan '16

Hi, Some of the Boost.DLL tests produce following warnings: ../boost/thread/win32/thread_primitives.hpp:175:83: warning: declaration of 'void* boost::detail::win32::GetModuleHandleA(const char*)' with C language linkage ../boost/detail/winapi/dll.hpp:47:1: warning: conflicts with previous declaration 'HINSTANCE__* GetModuleHandleA(boost::detail::winapi::LPCSTR_)' ../boost/thread/win32/thread_primitives.hpp:195:94: warning: declaration of 'int (__attribute__((__stdcall__)) * boost::detail::win32::GetProcAddress(void*, const char*))()' with C language linkage ../boost/detail/winapi/dll.hpp:82:1: warning: conflicts with previous declaration 'int (__attribute__((__stdcall__)) * GetProcAddress(boost::detail::winapi::HMODULE_, boost::detail::winapi::LPCSTR_))()' Andrey, Vicente what's the best way to resolve such issues? -- Best regards, Antony Polukhin

5 12

[qvm] deduce_xx traits wouldn't introduce ODR issues.
by Vicente J. Botet Escriba 31 Dec '15

31 Dec '15

Hi, I wonder if the deduce_xx traits wouldn't introduce ODR issues. Remember the TBoost.Conversion library where conversion between two types was customizable. The fact that deduce_xx traits have two types would promote ODR as there is no one type that is expected to do the customization. I believe that changing the default to something depending on the first argument will be better than using the specific qvm type as result. If this is not enough, you could add symbolic operations taken the result type as parameter, e.g. if a+b is not something specified by A, the user could use sum<C>(a,b) Forget my comment if there is no ODR issue. Best, Vicente

7 33

[dll] ready for master branch. Please merge
by Antony Polukhin 29 Dec '15

29 Dec '15

Hi, Boost.DLL is ready to appear in next release of Boost. Please, merge the DLL related changes into the master branch of boostorg/boost (changes for the develop branch were merged here: https://github.com/boostorg/boost/pull/94) Thanks! -- Best regards, Antony Polukhin

2 2

[qvm] Today is the last day of QVM formal review extended period
by Adam Wulkiewicz 23 Dec '15

23 Dec '15

Dear Boost Community! Today is the last day of the extended period of QVM library formal review. Since now we received 4 reviews. I encourage you to send more, there is still some time left. I'd like to thank all of you who have sent reviews as well as those who have taken part in the discussions. I'm going to wait for additional reviews a few days in case someone wanted to send one after the end of the review period. Does any of you plan to do it? Regards, Adam

1 0

Broken Link
by Mudit Sharma 23 Dec '15

23 Dec '15

All, The boost.python link provided on this page is broken: http://www.boost.org/doc/libs/1_60_0/more/getting_started/windows.html (See Boost.Python in section 3) Can anyone fix this? Thanks M

2 1

[autoindex] Default building with an Index
by Edward Diener 22 Dec '15

22 Dec '15

The documentation for VMD supports building with an index but I had not made this the default situation. This is my mistake. Can I assume the official build of the docs for a release supports building with an index via autoindex ? If so I will change the jamfile to support this as the default for the future and assume any end-user wishing to regenerate the docs has autoindex support also as part of the distribution as long as my jamfile is setup correctly for autoindex.

2 1

[doc] Releases 1.59 and 1.60 missing some tools documentation
by Edward Diener 22 Dec '15

22 Dec '15

In the 1.60 release, and I also just noticed in at least the 1.59 release also, the documentation links to the Release and Regression tools go to an invalid URL. Also while the documentation link to Boost.Build goes to a general explanation page the subsequent documentation link to Documentation goes to an invalid URL. Is this what we want, and that the end-user should have to "build" the documentation ? It seems doubtful, considering what a trial it often is for developers themselves to build the documentation given the tools available to do so. I think that this needs to be corrected in upcoming releases.

1 0

[regression] run.py merge option
by Antony Polukhin 22 Dec '15

22 Dec '15

Hi, How hard would it be to add a --merge option to run.py? Motivation: I'm experimenting with running all the regression tests on TravisCI https://github.com/apolukhin/boost_indirect_testing. Unfortunately, it has some hard limits, so a task can not work more than 2 hours. I've ended up splitting all the Boost tests by libraries and running tests on per library basis. Unfortunately, when the test results are send to server, only one library result is displayed in resulting matrix (search http://www.boost.org/development/tests/develop/developer/summary.html for indirect_travisci_tests) So I'd like to get a --merge option, that will allow merge of all the results by tester_name+revision. For example if results for 'geometry' and 'any' are sent with tester name `indirect_travisci_tests` and revision 74f85d, then show them in a single column. This may be also useful for those test runners that run tests on embedded or emulated devices (running all the Boost tests on emulated MIPS device may take a few weeks; running the tests on multiple emulated MIPS devices will speed up things) -- Best regards, Antony Polukhin

1 0

Software Freedom Conservancy Support
by Jon Kalb 22 Dec '15

22 Dec '15

This is not a technical message, but instead focuses on Boost Administration. Software Freedom Conservancy in a Financial Fight for its Life Software Freedom Conservancy, the non-profit home of Boost is facing an existential threat. Historically, Conservancy has been funded by corporate donations. This works great when it works, but a management shake-up, change in priorities, or a bad quarter at a large donor can derail the organization¹s programs. It has become obvious that Conservancy must move to a Supporter-driven funding model, where individuals who believe in Conservancy¹s mission of supporting open source projects, such as Boost, make a personal commitment to support that effort. Conservancy's fundraiser, found at https://sfconservancy.org/supporter/, is centered around asking individuals who care about the work that Conservancy does to donate $120/year, or just $10/month, to support the organization. Conservancy seeks about 2,500 Supporters to continue its current work, and 750 Supporters to continue a ³bare minimum² of services to its projects. What does this mean to Boost? Boost receives a myriad of important services (see https://sfconservancy.org/members/services/ ) from Conservancy. We¹ve relied on Conservancy since 2007 to provide them. Here are some of the things that Conservancy does for Boost that are in the ³bare minimum² category: * Dealing with all the financial and contractual details regarding our annual C++ Now conference. It was BoostCon that brought Boost and Conservancy together. C++Now 2016 will the the tenth annual BoostCon and it is a tribute to what we¹ve accomplished working together. * Handle our Google Summer of Code payments and travel, including handling all financial transactions with Google to receive and then disperse the money. * Coordinating travel reimbursements for Boost contributors (both developers and students) to attend conferences. * Receiving and tracking all donations to Boost. * Keeping the non-profit status for us so that we don't have to form our own org and file our own paperwork. As the Chair of the Boost Steering Committee, I cannot overstate how important this is to our existence as an organization. Here are some of the services Boost has received in the wider category: * Dealing with questions from the community (including license-governing bodies like OSI) about Boost's license. * Discussing the issue of copyright governance and contributions with large corporations who want their employees to contribute to Boost but need legal assurances or have questions relating to Boost's license or contribution policies. * Reviewing and handling licensing terms of third-party software that relate to Boost in some way, and giving us feedback and answers about issues related to it. * General legal consulting on issues that we run into as an open source non-profit. As you can see, Boost really relies on the important work of Conservancy. Support from Boost Boost, like all of Conservancy¹s projects, contributes 10% of our revenue to Conservancy¹s general fund. (The other 90% is maintained and administered by Conservancy at the direction of the Boost Steering Committee to advance the Boost project.) But that 10% of revenue from all Conservancy¹s member projects doesn¹t add up to enough to even employee one full time person, let alone the already overworked staff of three that Conservancy has. Donors must make up the difference. When Conservancy launched its fundraising effort, I sent out a request to past BoostCon/C++Now attendees asking for support and I¹m proud and delighted to say that a number of Boost community members have already stepped up. One told me that her company will be matching her support. Boost is one of Conservancy¹s oldest and largest projects, so it is right that Boost community members make up a fair proportion of its supporters. I encourage you to choose Conservancy as one of your charitable gifts this holiday season. (Conservancy is a 501(c)(3) charity incorporated in New York, and donations are typically deductible on U.S. taxes.) Please visit: https://sfconservancy.org/supporter/ If you are able to join the others from the Boost community that are making this gift, please let me know. I¹d like to personally thank you. Jon Kalb Chair, Boost Steering Committee

1 0

Becoming Maintainer of the Iterator Library
by Nathan Wilson 21 Dec '15

21 Dec '15

Hi all, There was talk on the mailing list a few months back, and was apparently discussed at CppCon in September, about becoming a Library Maintainer. This was pertaining to Libraries which are either being maintained by the CMT, or as Edward Diener mentioned, Libraries which aren't in the CMT's hands but the current maintainer(s) don't have time to devote to maintaining the particular library. That said, after having discussed it with a few people outside the mailing list, I would like to volunteer to become a Maintainer of Boost's Iterator Library. I have not been active on Boost's mailing list, but have participated in the C++ Standardization Process with the paper Delimited Iterators (http://open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4257.html) which will be in the Library Technical Specification 2. I have also submitted/committed some Patches in Clang as well. I just wanted to mention those couple of things as a point of reference so this didn't seem entirely random. Anyway, I'd be really excited to help contribute and help Boost by becoming a Maintainer of the Iterator Library. I do have some concern about compiling on various versions of Windows/OSX though. I have a Windows 8.1 machine and could obviously use Visual Studio, but I'm not too sure about verification of older Windows/OSX versions. On Linux I can certainly create VMs for various distros. If anyone has some best practices or advice about handling different OS distros/versions, that would be great. Please let me know if there are any questions. Thank you, Nathan

3 4

[smart_ptr] Moving cast for unique_ptr
by Karolin Varner 21 Dec '15

21 Dec '15

Hi all! There is the family of boost pointer cast (boost::static_pointer_cast, boost::dynamic_pointer_cast, ...) that allow a developer to write generic code by casting pointers regardless of whether they are some smart pointer (e.g. shared_ptr) or plain pointers. However, those functions have not been implemented for unique_ptr, because they create a copy of their pointer and unique_pointers can not be copied. In my case I still needed to cast some unique_ptr and since it's ok to move unique_ptrs I wrote a function that does exactly that. The code is below – Comments are very, very welcome. It works for my case, but I am sure it is not as generic and safe as it should be ;) . Specifically, for a library, it should be made to work on any kind of smart/plain pointer. Not just unique_ptr. Is there any interest to include a boost::static_moving_pointer_cast and the other types of casts in boost? Best, Karolin /// Dynamic cast a unique_ptr. /// /// This function shall move the pointer in in_ptr, into /// a new unique_pointer of the desire type, dynamic_casting /// it in the process. /// In given pointer shall contain a NULL pointer afterwards. /// /// If unsuccessful, function shall throw an error and leave /// in_ptr unmodified. /// /// This behaviour contrasts a bit with the behaviour of the /// normal dynamic_cast: /// 1. dynamic_cast copies objects, this moves them since /// unique_pointers can not be copied. /// 2. dynamic_cast returns a NULL pointer if the pointer to /// cast is of an incomplete type, this throws /// incomplete_cast instead, to ease error handling. /// /// @tparam T The type to convert to (as non-pointer) /// @tparam F The type to convert from (as non-pointer) /// @param in_ptr The unique_ptr to cast /// @return in_ptr, cast to the desired type template<typename T, typename F> std::unique_ptr<T> dynamic_moving_pointer_cast(std::unique_ptr<F> &in_ptr) { // Exception safety: If The dynamic cast throws an error, // or of we throw incomplete_cast, in_ptr will still be // unmodified T *plain_out_ptr = dynamic_cast<F*>(in_ptr.get()); if (plain_out_ptr == NULL && in_ptr.get() != NULL) throw incomplete_cast(); // Exception safety: Both operations are noexcept in_ptr.release(); return std::unique_ptr<T>(plain_out_ptr); }

6 11

safe::map
by Karen Pease 21 Dec '15

21 Dec '15

Hi everyone - I'm new to boost-devel, and am a bit intimidated ;) I recently finished a project and I don't know if the boost community would have any interest in it, whether it's really "boost material" or not: https://github.com/KarenRei/safe-map The page goes into more detail, but the short of it is: after searching and a long conversation on StackExchange, I discovered that while there are threadsafe ordered-map containers out there, the threadsafety was a bit weak. For example, if you have Thread A iterating across the map and Thread B thread just happens to delete an element as A is passing by, A's iterator becomes invalidated and the program crashes - even in a supposedly "threadsafe" map. For the type of multithreaded cache that I needed, I needed a structure that had the thread safety level of a filesystem - you know, where multiple processes can have file descriptors open at a time and one process might even potentially delete a file that another is accessing, without leading to a system crash. And that's basically what I implemented: safe::map, which not only ensures that basic operations on the container itself are threadsafe, but that everything you do with the iterators - even deleting elements out of the map that other iterators are pointing to - is also threadsafe. It does this by implementing reference counting on the elements in the map and flagging elements for deletion rather than deleting them immediately. A more detailed description of usage, performance, implementation, use cases, etc is on the project page. The project comes with a test suite which launches a number of threads that endlessly randomly tweak and iterate around the map with every function available to them. Does this sound like something that might be useful in boost (after whatever changes would be required)? If there's no interest, no harm done :) - kv, Karen

3 2

[Travis] All boostorg builds stalled?
by Louis Dionne 20 Dec '15

20 Dec '15

Hi, All of Hana's builds are currently stalled [1]. It has been like this for 2 or 3 days. I tried contacting Travis' support, but they are in vacation until January 4th. It also seems like the builds for Predef have been stalled for a while [2]. Perhaps other libraries are also touched. Strangely, builds for non-Boost repositories are not stalled, since I can build personal projects just fine. Does anyone know what might be happening? Louis [1]: https://travis-ci.org/boostorg/hana/builds [2]: https://travis-ci.org/boostorg/predef/builds/97532851

2 2

[gsoc]Seeking Guidance
by Ibrahim Dalal 20 Dec '15

20 Dec '15

Hi I am a sophomore, majoring in Computer Science. I am also a GSoC'16 aspirant. Its the first time I would be contributing to an open source project. Can someone please guide to a small project/patch suitable for a beginner? I have familiarity with C++ programming language along with basic understanding of C and Python. Also have some elementary knowledge of Git. Thanks

3 2

Boost 1.60.0 has been released
by Marshall Clow 18 Dec '15

18 Dec '15

Release 1.60.0 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 one new library and numerous enhancements and bug fixes for existing libraries. New Libraries * VMD: Variadic Macro Data library, from Edward Diener For details, including download links, see http://www.boost.org/users/news/version_1.60.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.60.0/ Tom Kent has made pre-built windows binaries, and they are available at: https://sourceforge.net/projects/boost/files/boost-binaries/1.60.0/ 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 Vladimir Prus Rene Rivera Marshall Clow Eric Niebler Daniel James Beman Dawes

2 1

[variant] Opinion on boost::safe_get<> and default boost::get<> behavior
by Antony Polukhin 18 Dec '15

18 Dec '15

Hi all, I'm in doubt and would like to hear opinions on the following issue. boost::get for boost::variant was not making any compile time checks, resulting in runtime errors where a compile time error must be: boost::variant<int, string> v(100); boost::get<bool>(&v); // returns NULL instead of compile time error boost::get<bool>(v); // throws exception on runtime instead of compile time error Now we have an implementation of compile time checked get in a separate branch at git: boost::variant<int, string> v(100); boost::safe_get<bool>(&v); // compile time error boost::safe_get<bool>(v); // compile time error boost::unsafe_get<bool>(&v); // returns NULL instead of compile time error boost::unsafe_get<bool>(v); // throws exception on runtime instead of compile time error I'm in doubt, what the default behavior of boost::get must be: * safe_get behavior is much closer to Standard Library behavior (just like std::get for tuples) and allows to avoid errors in user code * unsafe_get behavior is same as behavior of old boost::get and won't break user's code if boost::get is used in some generic contexs What's your opinion? -- Best regards, Antony Polukhin

10 13

[QVM] Boost.QVM formal review is ongoing
by Adam Wulkiewicz 18 Dec '15

18 Dec '15

Dear Boost community, It seems that there are some problems with gmane.org related to handling of messages sent to many mailing lists at once. Therefore I'm reposting the information about the formal review. I appologize those of you who recieve this message for the second time. The formal review of Emil Dotchevski's QVM library begined on 7th Dec and it ends on 16th Dec. Boost QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications. While it provides its own quaternion, matrix and vector types, it is designed to work primarily with user-defined types through user specializations of the q_traits, v_traits and m_traits templates. QVM's source code is available on Github: https://github.com/zajo/boost-qvm Full documentation is also viewable on Github: http://zajo.github.io/boost-qvm/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here: http://www.boost.org/community/reviews.html We await your feedback! Best regards, Adam Wulkiewicz

4 6

[qvm] Formal review for QVM
by Adam Wulkiewicz 18 Dec '15

18 Dec '15

Dear Boost community, The formal review of Emil Dotchevski's QVM library begins on 7th Dec and ends on 16th Dec. Boost QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications. While it provides its own quaternion, matrix and vector types, it is designed to work primarily with user-defined types through user specializations of the q_traits, v_traits and m_traits templates. QVM's source code is available on Github: https://github.com/zajo/boost-qvm Full documentation is also viewable on Github: http://zajo.github.io/boost-qvm/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here: http://www.boost.org/community/reviews.html We await your feedback! Best regards, Adam Wulkiewicz

6 22

QVM Review
by Phil Endecott 17 Dec '15

17 Dec '15

Dear All, This is my review of Emil Dotchevski's QVM library. Thank you to Emil for offering this code. I believe that Boost and/or the standard library would benefit from vectors and matrices. Unfortunately I don't think that this proposal is what is needed, and I feel it should not be accepted. I have previously posted my thoughts about the terseness of the identifiers used and the use of operator,; I won't repeat the details here but in summary I find the syntax not to my taste, and not suitable for "public" code. Boost should aim to promote best practice, and I think this library falls short. Now, it's not unusual to find libraries that have interfaces that we don't like. Often we'll use them anyway because the features that the libraries provide outweigh the pain of using them. Does this apply in the case of QVM? Actually since first looking I've found that it does have more functionality than I thought - for example, I've only just found that it has functions to create matrices representing rotations (but not any other affine transformations) and to compute the inverse of a matrix (but not the determinant). But there's still not enough meat here for me to think it's worth using. If this were a comprehensive matrix algebra library, or a computational geometry library, or a SIMD library, then it might be worth putting up with the syntax. But it isn't, it's just a medium-size collection of operators and functions for quaternions, vectors and matrices that many projects will already having amongst their own local utilities. What it does offer is the ability to wrap existing matrix and vector classes and use a single unified syntax for all of them. It's just a shame that the single unified syntax is not the one I want to use! It is interesting to contrast QVM with Boost.Polygon and Boost. Geometry. The similarity is that both of these also wrap existing classes (for e.g. points) by traits class specialisations. When these were reviewed we discussed extensively how support for this compromised the friendliness of the syntax, i.e. the need to write get<0>(p) rather than p.x. What we ended up with there was I think the best that we could do, and it was probably worthwhile because of the substantial core functionality of each of those libraries. In my opinion, QVM doesn't reach that threshold. To address some of the "standard questions": I've not looked at the code, only the docs; I've spent a couple of hours this time and also looked when it was first proposed; and yes I do use vectors and matrices in my own code, for various graphics and cartographic purposes. Regards, Phil.

4 7

Re: [boost] [Boost-users] Boost 1.60.0 rc1 is now available
by Marshall Clow 17 Dec '15

17 Dec '15

Thanks to everyone for testing and reporting back the problems with the RC. I have pinged Vicente about the Boost.Thread problem, and Sebastian about the Boost.PropertyTree warning supression patches. Antony is looking into the Boost.LexicalCast issue. After surveying the other release managers, none of these issues is worth holding up the release for (which would probably stretch to after the new year). We're going to "go with what we have" for the 1.60.0 release, and get these problems fixed for 1.61.0 -- Marshall

1 0

Boost 1.58 linking error with Mongo 3.2
by Ameerkhan Mohamed 17 Dec '15

17 Dec '15

Hi, I am planning to use 3.2 mongo version. Hence i built client library of mongo 3.2 with pre-built boost library of 1.58. Both libraries are built under 64 bit configuration. Lib created successfully. When i integrate this libmongoclient-s.lib with my project i faced some linking error. Some of the sample error is :: Error LNK2001 unresolved external symbol "class boost::filesystem::file_status __cdecl boost::filesystem::detail::status(class boost::filesystem::path const &,class boost::system::error_code *)" (?status@detail@filesystem@boost @@YA?AVfile_status@23@AEBVpath@23@PEAVerror_code@system@3@@Z) StoreGrid_Head Error LNK2001 unresolved external symbol "class boost::system::error_code __cdecl boost::filesystem::detail::dir_itr_close(void * &)" (?dir_itr_close@detail @filesystem@boost@@YA?AVerror_code@system@3@AEAPEAX@Z) StoreGrid_Head Guide me on this issue please. Regards, Ameerkhan M -- Thanks and Regards Ameerkhan M Software Engineer Vembu Technologies

1 0

Re: [boost] [Boost-announce] Boost 1.60.0 rc1 is now available
by Jan Mikkelsen 17 Dec '15

17 Dec '15

Hi, (Resending to avoid bouncing on the lists.) I can build the libraries on FreeBSD 10.2 with clang 3.7 and gcc 5.2 in various modes. However, with both clang 3.7 and gcc 5.2 the following program fails to compile: #define BOOST_MOVE_USE_STANDARD_LIBRARY_MOVE #include <boost/thread.hpp> int main() { } This works fine with the same compilers and boost 1.59. The difference seems to be caused a change to boost/thread/detail/thread_group.hpp to use boost::csbl::unique_ptr<> instead of std::auto_ptr<>. Diff showing the change between 1.59 and 1.60 in thread_group.hpp and the compiler error messages below. Regards, Jan Mikkelsen $ diff -u thread/detail/thread_group.hpp ../../boost-1_60/boost/thread/detail/thread_group.hpp --- thread/detail/thread_group.hpp 2015-12-17 01:08:28.000000000 +1100 +++ ../../boost-1_60/boost/thread/detail/thread_group.hpp 2015-12-17 01:20:56.000000000 +1100 @@ -6,6 +6,7 @@ // (C) Copyright 2007-9 Anthony Williams #include <list> +#include <boost/thread/csbl/memory/unique_ptr.hpp> #include <boost/thread/shared_mutex.hpp> #include <boost/thread/mutex.hpp> #include <boost/thread/lock_guard.hpp> @@ -75,7 +76,7 @@ thread* create_thread(F threadfunc) { boost::lock_guard<shared_mutex> guard(m); - std::auto_ptr<thread> new_thread(new thread(threadfunc)); + boost::csbl::unique_ptr<thread> new_thread(new thread(threadfunc)); threads.push_back(new_thread.get()); return new_thread.release(); } $ g++5 -std=c++14 -isystem /usr/local/include/boost-1_60 twio/test_thread.cpp In file included from /usr/local/include/boost-1_60/boost/thread/csbl/memory/unique_ptr.hpp:16:0, from /usr/local/include/boost-1_60/boost/thread/detail/thread_group.hpp:9, from /usr/local/include/boost-1_60/boost/thread/thread.hpp:13, from /usr/local/include/boost-1_60/boost/thread.hpp:13, from twio/test_thread.cpp:2: /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp: In constructor 'boost::movelib::unique_ptr<T, D>::unique_ptr(boost::movelib::unique_ptr<T, D>&&)': /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:530:29: error: 'move_if_not_lvalue_reference' is not a member of 'boost' : m_data(u.release(), ::boost::move_if_not_lvalue_reference<D>(u.get_deleter())) ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:530:68: error: expected primary-expression before '>' token : m_data(u.release(), ::boost::move_if_not_lvalue_reference<D>(u.get_deleter())) ^ In file included from /usr/local/include/boost-1_60/boost/thread/csbl/memory/unique_ptr.hpp:16:0, from /usr/local/include/boost-1_60/boost/thread/detail/thread_group.hpp:9, from /usr/local/include/boost-1_60/boost/thread/thread.hpp:13, from /usr/local/include/boost-1_60/boost/thread.hpp:13, from twio/test_thread.cpp:2: /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp: In constructor 'boost::movelib::unique_ptr<T, D>::unique_ptr(boost::movelib::unique_ptr<Y, D>&&, typename boost::move_upd::enable_up_moveconv_constr<T, D, U, E>::type*)': /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:552:29: error: 'move_if_not_lvalue_reference' is not a member of 'boost' : m_data(u.release(), ::boost::move_if_not_lvalue_reference<E>(u.get_deleter())) ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:552:68: error: expected primary-expression before '>' token : m_data(u.release(), ::boost::move_if_not_lvalue_reference<E>(u.get_deleter())) ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp: In member function 'boost::movelib::unique_ptr<T, D>& boost::movelib::unique_ptr<T, D>::operator=(boost::movelib::unique_ptr<T, D>&&)': /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:581:26: error: 'move_if_not_lvalue_reference' is not a member of 'boost' m_data.deleter() = ::boost::move_if_not_lvalue_reference<D>(u.get_deleter()); ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:581:65: error: expected primary-expression before '>' token m_data.deleter() = ::boost::move_if_not_lvalue_reference<D>(u.get_deleter()); ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp: In member function 'typename boost::move_upd::enable_up_moveconv_assign<T, D, U, E, boost::movelib::unique_ptr<T, D>&>::type boost::movelib::unique_ptr<T, D>::operator=(boost::movelib::unique_ptr<Y, D>&&)': /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:603:26: error: 'move_if_not_lvalue_reference' is not a member of 'boost' m_data.deleter() = ::boost::move_if_not_lvalue_reference<E>(u.get_deleter()); ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:603:65: error: expected primary-expression before '>' token m_data.deleter() = ::boost::move_if_not_lvalue_reference<E>(u.get_deleter()); ^ $ clang++37 -std=c++14 -isystem /usr/local/include/boost-1_60 twio/test_thread.cpp In file included from twio/test_thread.cpp:2: In file included from /usr/local/include/boost-1_60/boost/thread.hpp:13: In file included from /usr/local/include/boost-1_60/boost/thread/thread.hpp:13: In file included from /usr/local/include/boost-1_60/boost/thread/detail/thread_group.hpp:9: In file included from /usr/local/include/boost-1_60/boost/thread/csbl/memory/unique_ptr.hpp:16: /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:530:67: error: 'D' does not refer to a value : m_data(u.release(), ::boost::move_if_not_lvalue_reference<D>(u.g... ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:353:26: note: declared here template <class T, class D = default_delete<T> > ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:530:38: error: no member named 'move_if_not_lvalue_reference' in namespace 'boost' : m_data(u.release(), ::boost::move_if_not_lvalue_reference<D>(u.g... ~~~~~~~~~^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:552:67: error: 'E' does not refer to a value : m_data(u.release(), ::boost::move_if_not_lvalue_reference<E>(u.g... ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:548:29: note: declared here template <class U, class E> ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:552:38: error: no member named 'move_if_not_lvalue_reference' in namespace 'boost' : m_data(u.release(), ::boost::move_if_not_lvalue_reference<E>(u.g... ~~~~~~~~~^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:581:64: error: 'D' does not refer to a value m_data.deleter() = ::boost::move_if_not_lvalue_reference<D>(u.get_... ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:353:26: note: declared here template <class T, class D = default_delete<T> > ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:581:35: error: no member named 'move_if_not_lvalue_reference' in namespace 'boost' m_data.deleter() = ::boost::move_if_not_lvalue_reference<D>(u.get_... ~~~~~~~~~^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:603:64: error: 'E' does not refer to a value m_data.deleter() = ::boost::move_if_not_lvalue_reference<E>(u.get_... ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:597:29: note: declared here template <class U, class E> ^ /usr/local/include/boost-1_60/boost/move/unique_ptr.hpp:603:35: error: no member named 'move_if_not_lvalue_reference' in namespace 'boost' m_data.deleter() = ::boost::move_if_not_lvalue_reference<E>(u.get_... ~~~~~~~~~^ 8 errors generated. > On 15 Dec 2015, at 02:54, Marshall Clow <mclow.lists(a)gmail.com <mailto:mclow.lists@gmail.com>> wrote: > > Release candidate files for 1.60.0 are available at: http://boost.cowic.de/rc/ <http://boost.cowic.de/rc/> > > As always, the release managers would appreciate it if you download > the candidate of your choice and give building it a try. Please report > both success and failure, and anything else that is noteworthy. > > This helps ensure the candidates build OK before we push them out to SourceForge. > > The files (and associated md5s) are: > MD5 (boost_1_60_0_rc1.7z) = 7ce7f5a4e396484da8da6b60d4ed7661 > MD5 (boost_1_60_0_rc1.tar.bz2) = 65a840e1a0b13a558ff19eeb2c4f0cbe > MD5 (boost_1_60_0_rc1.tar.gz) = 28f58b9a33469388302110562bdf6188 > MD5 (boost_1_60_0_rc1.zip) = 0cc5b9cf9ccdf26945b225c7338b4288 > > Thanks! > > -- The release managers > > P.S. Release notes are here: http://www.boost.org/users/history/version_1_60_0.html <http://www.boost.org/users/history/version_1_60_0.html> > > _______________________________________________ > Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost-announce <http://lists.boost.org/mailman/listinfo.cgi/boost-announce>

1 0

QVM formal review extension request
by Adam Wulkiewicz 16 Dec '15

16 Dec '15

Dear Boost Community! The number of reviews we received so far is too small to decide wether or not QVM should be a part of Boost. Therefore I request to extend the review period by a week to 23rd Dec. I'm aware that the time of year may be busy and that we're in the middle of Boost release. I hope that the extension would allow you to find time to write a short piece of review. -----The original announcement----- The formal review of Emil Dotchevski's QVM library is ongoing. Boost QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications. While it provides its own quaternion, matrix and vector types, it is designed to work primarily with user-defined types through user specializations of the q_traits, v_traits and m_traits templates. QVM's source code is available on Github: https://github.com/zajo/boost-qvm Full documentation is also viewable on Github: http://zajo.github.io/boost-qvm/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here: http://www.boost.org/community/reviews.html We await your feedback! Best regards, Adam Wulkiewicz

1 0

Boost 1.60.0 rc1 is now available
by Marshall Clow 15 Dec '15

15 Dec '15

Release candidate files for 1.60.0 are available at: http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. The files (and associated md5s) are: MD5 (boost_1_60_0_rc1.7z) = 7ce7f5a4e396484da8da6b60d4ed7661 MD5 (boost_1_60_0_rc1.tar.bz2) = 65a840e1a0b13a558ff19eeb2c4f0cbe MD5 (boost_1_60_0_rc1.tar.gz) = 28f58b9a33469388302110562bdf6188 MD5 (boost_1_60_0_rc1.zip) = 0cc5b9cf9ccdf26945b225c7338b4288 Thanks! -- The release managers P.S. Release notes are here: http://www.boost.org/users/history/version_1_60_0.html

4 4

Boost 1.60.0 beta 1 Release Candidate 4 available for testing
by Marshall Clow 15 Dec '15

15 Dec '15

After far too long, release candidate files for 1.60.0 beta 4 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. Changes since rc3: * Boost.Test has been updated and now builds on Visual Studio Changes since rc1: * Boost.Sprit has been updated and Boost.Log now builds. * Boost.Math has been updated and now builds. Known issues (which will not be fixed for the beta): * Errors when building Boost.TypeErasure for older versions of Visual Studio. * Boost.Test fails when building on Darwin with gcc 4.9.2 The files (and associated md5s) are: MD5 (boost_1_60_0_b1_rc4.7z) = 63530c9594b24f56e5df79d910c9daeb MD5 (boost_1_60_0_b1_rc4.tar.bz2) = 29af12a1028536219a21517e953df4eb MD5 (boost_1_60_0_b1_rc4.tar.gz) = 74df7f5eb5e32f3a92b6141af3c6f541 MD5 (boost_1_60_0_b1_rc4.zip) = 90c25c34b64eb6cc88845ec5372938d7 Thanks! -- The release managers

8 16

Fwd: Re: [Boost-users] [boost-users][QVM] Boost.QVM formal review is ongoing
by Adam Wulkiewicz 15 Dec '15

15 Dec '15

It seems that you've send a response to the boost-users list and I'm guessing Emil is not a subscriber because he haven't responded. So I'm forwarding it to the developers mailing list. -----Original Message----- I'm not qualified to give a full review of this library beyond observing: 1 It looks very useful. 2 Boost prefers clarity to curtness. The naming is much too terse making the resulting code rather 'write-only'. I'd at least go for col_mat for col_m and transpose for transp etc. (I know any changes will be a big PITA but shows that asking sooner than later is a good idea for would-be Boost library authors ;-) 3 Documentation is OK, but I'd like many more examples of every function, and some much bigger fuller real-life examples showing use too. 4 Does this mesh at all with the quaternions in Boost.Math library? FWIW Paul PS If you build the Boost inspect tool \modular-boost\tools\inspect by running its jamfile, (and making sure that it is in your PATH) then from your /doc folder you can simply call > inspect > inspect.html and view any transgressions of the Boost rules in inspect.html - and, most important, any dud links. You may get a few false positives, but you can spot these easily. --- Paul A. Bristow Prizet Farmhouse Kendal UK LA8 8AB +44 (0) 1539 561830 _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

2 1

QVM formal review update
by Adam Wulkiewicz 15 Dec '15

15 Dec '15

Dear Boost Community! We're near the end of the QVM formal review period, it ends on 16th Dec. So far 11 people participated in discussions (not taking Emil nor me into account) and 2 reviews were sent. Do anyone of you need more time to ask questions, discuss, think, familiarize with QVM before sending a review? Are there people who would like to participate but haven't found enough free time so far? Basically I'm asking if anyone thinks that a review period should be extended? We appreciate your time and effort and of course kindly ask for sending reviews whenever you're ready. <TL;DR> -----The original announcement----- The formal review of Emil Dotchevski's QVM library is ongoing, it started on 7th Dec and it ends on 16th Dec. Boost QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications. While it provides its own quaternion, matrix and vector types, it is designed to work primarily with user-defined types through user specializations of the q_traits, v_traits and m_traits templates. QVM's source code is available on Github: https://github.com/zajo/boost-qvm Full documentation is also viewable on Github: http://zajo.github.io/boost-qvm/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here: http://www.boost.org/community/reviews.html We await your feedback! Best regards, Adam Wulkiewicz

1 0

safe integer library -- the scope
by Andrzej Krzemienski 14 Dec '15

14 Dec '15

Hi Robert, It is great to see this library getting into Boost. It fills an important gap, but it is only after a long while that I realized that, because the introductory part of the documentation does not stress it enough, and in fact it misled me a bit. My understanding is that safe<int> represents a high level abstraction of an integral number from mathematics: unlike raw type int, which represents a set of allowed operations on the underlying processor. You could say that raw type 'int' is only needed to efficiently implement higher level abstractions, like BigInt or safe<int> -- the two only differ in trade-offs between efficiency and the range of values they can represent. I was missing this in the introduction. Instead I got a somewhat negative impression that the goal of the library is to turn any UB into throwing exceptions (and thereby prevent any UB-based static analysis from detecting programmer errors). I would like to see the library in Boost, although I must admit the other parts do not sound that compelling as safe<int>. Regards, &rzej

6 27

Query About Boost Soc2016
by Arafat Khan 14 Dec '15

14 Dec '15

Respected Sir/Mam I am Arafat Dad Khan, I am a second year undergraduate student at Indian Institute of Technology Kharagpur. I wish to contribute to the Boost Library. I have decent *knowledge of Algorithms and Data Structures *and have consistently taken part in algorithmic competitions on websites such as Codechef and Spoj(Sphere online Judge ) You can view my profiles here http://www.spoj.com/SPOJ/users/adk/ and here https://www.codechef.com/users/adkcodeme I am *looking for potential mentors for Gsoc 2016* so that i start contributing by working on a small tasks first.I want develop requirements for my proposal by doing *initial background research on the topic*, and interact with the mentors and community to help identify expectations for projects . Regards Arafat Dad Khan Indian Institute of Technology Kharagpur

1 0

Reminder - Master branch closes for release on Sunday night
by Marshall Clow 11 Dec '15

11 Dec '15

I will be making the RC for the 1.60 release Monday morning. Changes that are not merged into master before then will NOT be in the 1.60 release. -- Marshall

1 0

[qvm] Terseness of syntax etc.
by Phil Endecott 11 Dec '15

11 Dec '15

Adam Wulkiewicz wrote: > The formal review of Emil Dotchevski's QVM library begins today > on 7th Dec and ends on 16th Dec. > Full documentation is also viewable on Github: > http://zajo.github.io/boost-qvm/ Following are some comments about the docs and syntax. This is based on an earlier look at the library when it was first announced and a quick look recently to see what has changed. I've not looked at the source code or tried to use the library. I wish that the docs started with a page showing how to use the library's built-in types. Currently, the first code that is presented shows how to define traits to make a user-supplied type work with the library. This is too advanced for the first page of the tutorial. The docs should start by showing how to do some high-school vector algebra using the built-in vector and matrix types. I find most of the identifiers too short. To give just a couple of examples: "transp" is used to mean "transpose". You save typing three letters, and get confusion with transparent, transport, etc. Then look at the names of some traits classes; elsewhere we have type_traits, allocator_traits, iterator_traits etc. all spelt out in full, but in qvm we have q_traits, v_traits and m_traits. I could go on but really almost every identifier is too short for my tastes. I had a quick think about how a struct with x,y,z members could be adapted. Am I right in thinking that it would be necessary to write accessors like this inside the traits specialisation: float ir(int i, xyz_vec const & v) { switch (i) { case 0: return v.x; case 1: return v.y; case 2: return v.z; } } ? If so, do we think that a compiler would successfully optimise that when it realised that x, y and z were in contiguous memory? (I guess you could also have an array of member pointers; would that work any better?) I'm really not a fan of the old operator% and now operator, syntax. To me, (v,XY) looks like you're forming a row-vector with two elements. Is there a reason why these accessors can't be written with function syntax, i.e. XY(v) ? Or, for matrices, something like element<4,2>(m) rather than (m,A<4,2>) ? I guess that what we'd really like to be able to do is to override operator. and write v.XY. There are proposals for adding operator. to the core language. Would those proposals support what is needed here? Actually, maybe this is closer to another proposal - the unified call syntax, which would make v.XY() equivalent to XY(v). I'll be interested to see what others think about these and other aspects of the proposal. Regards, Phil.

11 26

[QVM] Help with small example
by Rajaditya Mukherjee 10 Dec '15

10 Dec '15

I am trying to run boost::qvm on my machine. I am using MS Visual Studio 2013 with Boost 1.59 as the backend. #include <boost/qvm/all.hpp> #include <iostream> class float4 { public: float4(float a, float b, float c, float d) { container[0] = a; container[1] = b; container[2] = c; container[3] = d; } float container[4]; }; namespace boost { namespace qvm { template<> struct v_traits<float4> { static int const dim = 3; typedef float scalar_type; template <int I> static inline scalar_type &w(float4 & v) { return v.container[I]; } template <int I> static inline scalar_type r(float4 const & v) { return v.container[I]; } static inline scalar_type &iw(int i, float4 &v) { return v.container[i]; } static inline scalar_type ir(int i, float4 const & v) { return v.container[i]; } }; } } int main() { float4 vec(11.0,0.0,5.0,-6.0); std::cout << boost::qvm::mag(vec); (vec,boost::qvm::A<1>) = 112.0; std::cout << boost::qvm::mag(vec); } In the line *(vec,boost::qvm::A<1>) = 112.0, *I am getting an compiler error that says error C2563: mismatch in formal parameter list error C2568: ',' : unable to resolve function overload 1> d:\dropbox\programs\boost_qvm\include\boost\qvm\v_access.hpp(79): could be 'boost::qvm::vector_access_tag<I> boost::qvm::A(void)' 1> d:\dropbox\programs\boost_qvm\include\boost\qvm\m_access.hpp(78): or 'boost::qvm::matrix_access_tag<R,C> boost::qvm::A(void)' Any help ? Maybe I am doing something stupid ? Any help by Emil or anyone else is appreciated. *Rajaditya Mukherjee * *3rd Year Graduate Student* Dept. of Computer Science and Engineering The Ohio State University Columbus, Ohio Tel :- +1-(614)-271-4439 email :- rajaditya.mukherjee(a)gmail.com <mukherjee.62(a)osu.edu>, raj(a)rajaditya.com <mukherjr(a)cse.ohio-state.edu>

3 4

Master branch is open for merging
by Marshall Clow 10 Dec '15

10 Dec '15

Thanks to everyone for their patience; the master branch is now open for merging. Remember, we're coming up to a release, so please, no breaking changes. Thanks! -- Marshall

3 4

[Property_tree] error with ptree_serialization in 1.59
by David Bernstein 10 Dec '15

10 Dec '15

Hi Everyone, This is my first post here, hopefully I’m at the right place but if not please let me know where I should go. I have a C++ class which uses boost::property_tree and also includes <boost/property_tree/ptree_serialization.hpp>. This has been working nicely until I upgraded to V1.59 today and now I’m getting the compile error below. Any help with this would be greatly appreciated! Thanks, Dave /usr/local/include/boost/property_tree/ptree_serialization.hpp:66:24: error: no type named 'library_version_type' in namespace 'boost::archive' const bsa::library_version_type library_version( ~~~~~^ /usr/local/include/boost/property_tree/ptree_serialization.hpp:69:21: error: no member named 'library_version_type' in namespace 'boost::archive' if(bsa::library_version_type(3) < library_version){ I This e-mail is covered by the Electronic Communication Privacy Act, 18 U.S.C. Section 2510-2521 and may be legally privileged. If you have received this transmission in error, please notify the original sender immediately by return e-mail or by telephone at the telephone number provided above and delete/trash the original message from your system. Thank you for your assistance. The information contained herein is confidential information provided only for the use of the individual or entity for whom it was intended. If the reader of this message received it in error, is not the intended recipient, or if an attachment is made in error, the reader is hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited.

1 1

Using BOOST_AUTO_TEST_CASE_TEMPLATE but passing a list of test values too
by Paul A. Bristow 10 Dec '15

10 Dec '15

I want to test a (quite large) variety of user-defined types using Boost.Test. As a very contrived example, suppose I wanted to check numeric_limits digits for integer types I'd like to avoid a tediously long list like this BOOST_CHECK_EQUAL(std::numeric_limits<char>::digits, 8); BOOST_CHECK_EQUAL(std::numeric_limits<char>::digits, 16); BOOST_CHECK_EQUAL(std::numeric_limits<char>::digits, 32); ... and follow the example of BOOST_AUTO_TEST_CASE_TEMPLATE but allow a test value to be passed too, something like this: typedef boost::mpl::list<char, int, long> test_types; and a list of test values, perhaps like this typedef list_c<int, 8, 32, 64> test_values; (However it would be *far* more useful to be able to test strings and floats and User-defined types too). BOOST_AUTO_TEST_CASE_TEMPLATE_????(digits_test, T, test_types, test_values) { BOOST_CHECK_EQUAL(std::numeric_limits<T>::digits, test_values); } Has any Macro Guru produced a BOOST_AUTO_TEST_CASE_TEMPLATE_? that includes a list of test values? Or other suggestions. Thanks Paul --- Paul A. Bristow Prizet Farmhouse Kendal UK LA8 8AB +44 (0) 1539 561830

1 1

[qvn] Why doesn't QVM use [] or () to access vector and matrix elements?
by Vicente J. Botet Escriba 10 Dec '15

10 Dec '15

Hi, These operators could be used for views So instead of (m, <http://zajo.github.io/boost-qvm/operator_mod_rationale.html>A42) *= 42; we could have in C++11 ref(m)(4,2) *= 42; ref(m)[4][2) *= 42; In C++98 these could be less efficient than e.g. value<4,2>(m) *= 42; Best, Vicente

2 2

Segmented Tree Sequence documentation broken
by Vicente J. Botet Escriba 09 Dec '15

09 Dec '15

Hi, the link to Segmented Tree Sequence documentation in the review schedule and the Incubator is broken. https://det.github.io/segmented_tree_seq Vicente

2 2

[shared_ptr] Clang with Microsoft CodeGen in VS 2015 Update 1
by Beman Dawes 09 Dec '15

09 Dec '15

See http://blogs.msdn.com/b/vcblog/archive/2015/12/04/introducing-clang-with-mi… I tried building the Boost.Filesystem DLL with clang/c2 using the Visual Studio solution from libs/filesystem/test/msvc. As indicated the blog post, the following changes were needed in the project's properties: Configuration Properties General Platform Toolset : Clang 3.7 with Microsoft CodeGen (v140_clang_3_7) C/C++ General Warning Level : EnableAllWarnings (-Wall) Code Generation Enable C++ Exceptions: Yes (-fexceptions) Language Enable Run-Time Type Information: Yes (-frtti) Precompiled Headers Precompiled Header: Not using Precompiled Headers The operations.cpp compile failed with the following errors: 2> operations.cpp 2> In file included from ..\..\..\src\operations.cpp:44: 2> In file included from ../../../../..\boost/filesystem/operations.hpp:25: 2> In file included from ../../../../..\boost/filesystem/path.hpp:29: 2> In file included from ../../../../..\boost/shared_ptr.hpp:17: 2> In file included from ../../../../..\boost/smart_ptr/shared_ptr.hpp:28: 2> In file included from ../../../../..\boost/smart_ptr/detail/shared_count.hpp:29: 2> In file included from ../../../../..\boost/smart_ptr/detail/sp_counted_base.hpp:45: 2>../../../../..\boost/smart_ptr/detail/sp_counted_base_clang.hpp(29,1): error : cannot mangle this C11 atomic type yet 2> inline void atomic_increment( atomic_int_least32_t * pw ) 2> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2>../../../../..\boost/smart_ptr/detail/sp_counted_base_clang.hpp(34,1): error : cannot mangle this C11 atomic type yet 2> inline boost::int_least32_t atomic_decrement( atomic_int_least32_t * pw ) 2> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2>../../../../..\boost/smart_ptr/detail/sp_counted_base_clang.hpp(39,1): error : cannot mangle this C11 atomic type yet 2> inline boost::int_least32_t atomic_conditional_increment( atomic_int_least32_t * pw ) 2> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ So it looks like the clang/c2 toolset doesn't support atomics yet. The __c2__ and __c2_version__ macros allow detection of the clang/c2 toolset, could a workaround be added to shared_ptr? I know we don't usually worry about workarounds for preview (i.e. early beta) compiler releases, but the ability to add the clang/c2 toolset to local tests for library developers working on Windows will be a big plus IMO. --Beman PS: Has anyone figured out how to invoke clang/c2 from the command line?

3 6

boost::hash - different values for the same input?
by trafdev 09 Dec '15

09 Dec '15

Hi. As per hash_range docs (http://www.boost.org/doc/libs/1_59_0/doc/html/hash/reference.html#boost.has…) "This hash function is not intended for general use, and isn't guaranteed to be equal during separate runs of a program - so please don't use it for any persistent storage or communication." As per code (http://www.boost.org/doc/libs/1_59_0/boost/functional/hash/hash.hpp) it uses hash_combine_impl which doesn't use any random, process_id etc values which might change during new process launches. At the same time, in an example describing container usage in the shared memory (http://www.boost.org/doc/libs/1_59_0/doc/html/interprocess/allocators_conta…) boost::hash is being used: typedef boost::unordered_map < KeyType , MappedType , boost::hash<KeyType> ,std::equal_to<KeyType> , ShmemAllocator> MyHashMap; My question is: is it safe to use boost::hash in a shared (persistent) storage or it's safe only for a particular (non-pointer) types? In this case, boost::hash docs should be changed to mention this exceptions, because otherwise no one could use boost::hash in a shared memory containers.

1 0

Updated 1.60 release schedule
by Marshall Clow 09 Dec '15

09 Dec '15

Since we were late on the 1.60 release, we've updated the release schedule. The master branch is currently open for bugfixes and documentation changes ONLY. The master branch will close on Sunday night (Dec 12th). We will build an RC for the 1.60 release Monday, and if all goes well, release it on Thursday, December 17th. So get those bug fixes in before Sunday! -- Marshall

1 0

[qvm] Review announcement
by Phil Endecott 09 Dec '15

09 Dec '15

Adam Wulkiewicz wrote: > The formal review of Emil Dotchevski's QVM library begins > today on 7th Dec and ends on 16th Dec. Adam sent this announcement email to the boost@, boost-users@ and boost-announce(a)lists.boost.org lists. Which seems OK, except that as I have previously noted the gmane.org website seems to get confused by such messages; this announcement will have appeared on only the announce page at gmane.org and any followups that are sent to e.g. the boost@ list will not be displayed by gmane at all. You might argue that this is a gmane.org bug, and that is true, but on the other hand we do want everyone who might be interested to know about the review, and a quick look at email headers will show that many do use the gmane.org web interface to read these lists. I've previously suggested that whatever "how to be a review manager" documentation that exists should advise that announcements should be posted separately to each list. Perhaps no such documentation exists! (I'll post some comments about the actual proposal soon.) Regards, Phil.

2 1

[LOG] formatting_ostream API change
by Andrew Hundt 09 Dec '15

09 Dec '15

I had the following code, which worked in 1.58: #include <boost/log/trivial.hpp> #include <boost/exception/all.hpp> #include <boost/algorithm/string.hpp> /// @todo move elsewhere, because it will conflict with others' implementations of outputting vectors template<typename T> inline boost::log::formatting_ostream& operator<<(boost::log:: formatting_ostream& out, std::vector<T>& v) { out << "["; size_t last = v.size() - 1; for(size_t i = 0; i < v.size(); ++i) { out << v[i]; if (i != last) out << ", "; } out << "]"; return out; } I used it to output a std::vector<float> as follows: BOOST_LOG_TRIVIAL(trace) << “Real joint angles from FRI: " << realJointPosition << "\n"; However this now seems to fail in 1.59. I’ve created a github gist with the compiler output <https://gist.github.com/ahundt/5869dbd09e889b7153c3> in case that’s helpful as well. I see that the update recently had some breaking changes, what is the new way to provide the desired functionality? Thanks for your help. Cheers! Andrew Hundt

2 3

Boost release 1.60.0 beta 1 is now available from SourceForge
by Marshall Clow 08 Dec '15

08 Dec '15

Boost release 1.60.0 beta 1 is now available from SourceForge. See http://sourceforge.net/projects/boost/files/boost/1.60.0.beta.1/ For details of what's in the release, see http://www.boost.org/users/history/version_1_60_0.html. Note that the links to files on this web page are for the final release - use the SourceForge link above to get the beta files. Please download the beta, give it a try, and report any problems you encounter. Known issues: * Errors when building Boost.TypeErasure for older versions of Visual Studio. * Boost.Test fails when building on Darwin with gcc 4.9.2 The files (and associated md5s) are: MD5 (boost_1_60_0_b1.7z) = 63530c9594b24f56e5df79d910c9daeb MD5 (boost_1_60_0_b1.tar.bz2) = 29af12a1028536219a21517e953df4eb MD5 (boost_1_60_0_b1.tar.gz) = 74df7f5eb5e32f3a92b6141af3c6f541 MD5 (boost_1_60_0_b1.zip) = 90c25c34b64eb6cc88845ec5372938d7 Thanks, -- The Boost Release Team

2 1

Checking for #pragma GCC diagnostic push|pop availability
by Marshall Clow 08 Dec '15

08 Dec '15

Shane Turner wrote: > I found another issue with a bad compiler version check in > boost/interprocess/detail/config_begin.hpp before using "#pragma GCC > diagnostic push", which, for GCC, is only available at version 4.6.0 and > later. Since I'm using GCC 4.4.7, my compile fails. It looks to me like interprocess is the one that really needs fixing. [ There could be a lot of cleanup here, but that's for another time ] I will make a PR. -- Marshall I have found (in non-test code) #if defined(__GNUC__) && (__GNUC__*10000 + __GNUC_MINOR__*100 + __GNUC_PATCHLEVEL__ > 40800) type_traits/has_logical_not.hpp #if BOOST_GCC >= 40700 tuple/detail/tuple_basic.hpp #Effectively >= 40600 smart_ptr/shared_ptr.hpp smart_ptr/scoped_ptr.hpp smart_ptr/detail/shared_count.hpp #if defined(BOOST_GCC) && BOOST_GCC >= 40600 random/detail/disable_warnings.hpp random/detail/enable_warnings.hpp #if defined(__clang__) move/detail/std_ns_begin.hpp move/detail/std_ns_end.hpp #elif defined(__GNUC__) && !(defined(__INTEL_COMPILER) || defined(__ICL) || defined(__ICC) || defined(__ECC)) \ && (__GNUC__ * 100 + __GNUC_MINOR__) >= 406 log/detail/header.hpp log/detail/footer.hpp #if defined(__clang__) || (defined(__GNUC__) && !(defined(__INTEL_COMPILER) || defined(__ICL) || defined(__ICC) || defined(__ECC)) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))) lexical_cast/try_lexical_convert.hpp #if defined(BOOST_GCC) && (BOOST_GCC >= 40000) interprocess/detail/config_begin.hpp interprocess/detail/config_end.hpp #Effectively >= 40600 get_pointer.hpp

2 1

[boost-users][boost-announce][QVM] Formal review begins today
by Adam Wulkiewicz 07 Dec '15

07 Dec '15

Dear Boost community, The formal review of Emil Dotchevski's QVM library begins today on 7th Dec and ends on 16th Dec. Boost QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size with the emphasis on 2, 3 and 4-dimensional operations needed in graphics, video games and simulation applications. While it provides its own quaternion, matrix and vector types, it is designed to work primarily with user-defined types through user specializations of the q_traits, v_traits and m_traits templates. QVM's source code is available on Github: https://github.com/zajo/boost-qvm Full documentation is also viewable on Github: http://zajo.github.io/boost-qvm/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here: http://www.boost.org/community/reviews.html We await your feedback! Best regards, Adam Wulkiewicz

1 0

interest in an asynchronous linear algebra library?
by Oswin Krause 07 Dec '15

07 Dec '15

Hi list, Disclaimer: What I am proposing here does not exist (yet). But it will in the near future and if there is interest i would like to give something back to the boost community. I would like to propose a new library to boost: asynchronous blas. What is it and what can I do with it? It is a linear algebra library where all computations are carried out in an asynchronous manner on GPU and CPU. Computing a matrix-matrix product does not block the current thread but instead launches a task which at some point returns with a result, allowing the main thread to continue until the result is needed. GPU and CPU tasks can be started at the same time depending on each other (e.g. a CPU computation waits until the GPU returned some needed result and vice-versa) Why is this important? Which problems does it solve? Many linear algebra libraries are target towards either a) solving a few large linear algebra problems b) solving many small similar problems This library is targeted towards the middle ground: a medium amount of decently sized problems. Here the problem is that it is often hard to use all the computing resources available as a single problem will not exhaust the device resources and there is no easy way to launch several similar tasks in parallel. This problem occurs often in GPU computing where out-of-order execution of kernels is used to fill up the device. Similarly, it is often hard to make CPU and GPU work together as GPU tasks are asynchronous while CPU tasks are often synchronous and it is not straight forward to couple both without blocking either CPU or GPU. How does it work? Expression templates similar to boost::ublas are used to create a dependency graph: which object is used in which computations and which tasks have to wait to ensure a correct outcome? a simple case would be two independent computations like matrix A=prod(B,trans(B)); matrix C=prod(trans(B),B); a normal library like ublas would wait until A is computed before C is evaluated. Instead, it can be more efficient to just add the two tasks to a list and let worker threads execute them as soon as resources are available. First the computation of A is put into the graph and A is marked as "being written to" while B is marked as "being read". When C is added to the list, it does not depend on the first computation as several tasks can read from B at the same time. So another worker thread can grab the task and execute it. If we now add the task B += prod(D,prod(C,trans(D)); the library computes it as matrix temp = prod(C,trans(D); B += prod(D,temp). temp can be computed as soon as C is computed. But B can only be computed after A and temp are computed as we can only write to B after all previous tasks using B are finished. Are you qualified? I am main contributor to https://github.com/Shark-ML/Shark/ and as part of it I forked ublas https://github.com/Shark-ML/Shark/tree/master/include/shark/LinAlg/BLAS which now uses several linear algebra libraries as possible backends (ATLAS, openBLAS...). What is the timeline? I would start developing a minimal example ASAP based on the rewrite of ublas above. I would use a minimum set of features (only dense square matrices) and basic GPU support. Opinions? Best, Oswin

8 17

[asio] Any interest in a boost::asio::mockup_serial_port ?
by Damien Buhl 07 Dec '15

07 Dec '15

Dear Boost.Asio developers, I wanted to know if there was any interest for a mockup_serial_port_service, so that one might write cross platform unit-tests of code based on serial_port. I implemented this mockup this summer for a project where the best way to unit test some modules was to act as another peer on a serial port and needed to be doable on any platform supported by asio::serial_port. I find it quite useful, because there - is no need to use separate tools like socat on linux or install virtual COM ports applications on windows. Which ease the setup of the test environment - the fake serial port doesn't pollute the system where the test is run - many test cases can be run in parallel, as there is no native ressources involved. One might use it as this : > using namespace boost::asio; > > boost::thread simulate_writing_device([](){ > io_service ios; > basic_serial_port<mockup_serial_port_service> port{ios, "my_fake_serial_port"}; > > const std::string message = "Hello"; > > for (;;) { > boost::asio::write(port, buffer(message.data(), message.size())); > boost::this_thread::sleep_for(boost::chrono::seconds(1)); > } > > }); > > boost::thread simulate_reading_device([](){ > io_service ios; > basic_serial_port<mockup_serial_port_service> port{ios, "my_fake_serial_port"}; > > for (;;) { > char message[5]; > boost::asio::read(port, buffer(message, 5)); > std::cout << "received : " << std::string(message, 5) << std::endl; > } > > }); A short documentation is available here : http://goo.gl/24JnUg And the implementation is on github in a holdall library for the moment : https://goo.gl/E7KGdn It's a library whose goal is to shrink over the time as they get merged in upstreams project. Hopefully there is interest for this mockup_serial_port, and if so I'll cleanup the code some more and make a pull-request to Boost.Asio. Cheers from Berlin where meetingcpp already ended :'-( -- Damien Buhl

2 2

[fiber] ready for next review
by Oliver Kowalke 06 Dec '15

06 Dec '15

As request, I'd like to announce that boost.fiber has addressed the requests of the last review. Especially migrating fibers between threads is supported - sub-directory 'examples' contains code demonstrating work-sharing and work-stealing. boost.fiber: github.com/olk/boost-fiber/tree/develop (branch develop) requires boost.context (branch develop) Oliver

2 22

Boost 1.60.0 beta 1 Release Candidate 2 available for testing
by Marshall Clow 04 Dec '15

04 Dec '15

Release candidate files for 1.60.0 beta 1 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. Changes since rc1: * Boost.Sprit has been updated and Boost.Log now builds. * Boost.Math has been updated and now builds. Known issues: * Errors when building libraries for visual studio: test and type_erasure. * Boost.Test fails when building on Darwin with gcc 4.9.2 The files (and associated md5s) are: MD5 (boost_1_60_0_b1_rc2.7z) = dd38daa9378a6002fc12da0cab695511 MD5 (boost_1_60_0_b1_rc2.tar.bz2) = f3c9ffc14db3b2e55c7c5c703e69883d MD5 (boost_1_60_0_b1_rc2.tar.gz) = 89365262443cc16990b69f8e4b8b47ab MD5 (boost_1_60_0_b1_rc2.zip) = 3389bd4595a989fe95966440cbe45ca9 Thanks! -- The release managers

7 12

thread_specific crashes the application when it is in a .so file
by George Georgiev 03 Dec '15

03 Dec '15

Hi, Is there a known issue about boost::thread_specific when a global thread_specific object is in a .so file? The exact same code replacing it with thread_local boost::unique_ptr<Foo> works. By the way is there a macro that determines is thread_local supported from the compiler or not? Thanks, George

3 3

Documentation for boostbook
by Soul Studios 02 Dec '15

02 Dec '15

I've seen the existing documentation, and wasn't impressed- is there a better site for details on this? Something with at minimum, a copy of the DTD and an example .xml file? Thanks, Matt

1 0

compilation errors with ublas / cppad
by Peter Caspers 30 Nov '15

30 Nov '15

Hi, I think this has been asked before, but since I am not aware of any answer, I would like to bring up the topic again: When using CppAD::AD<double> with boost ublas, certain compilation errors show up. I attach a small example (ublas_cppad.cpp) and the (start of the) error messages I get (compilation_errors.txt, produced with boost 1.59.0, g++ 4.9.3, CppAD-20151124). The problem is in matrix_assign.hpp; when changing template<class E1, class E2, class S> BOOST_UBLAS_INLINE bool equals (const matrix_expression<E1> &e1, const matrix_expression<E2> &e2, S epsilon, S min_norm) { return norm_inf (e1 - e2) < epsilon * std::max<S> (std::max<S> (norm_inf (e1), norm_inf (e2)), min_norm); } to template<class E1, class E2, class S> BOOST_UBLAS_INLINE bool equals (const matrix_expression<E1> &e1, const matrix_expression<E2> &e2, S epsilon, S min_norm) { S tmp = norm_inf (e1 - e2); return tmp < epsilon * std::max<S> (std::max<S> (norm_inf (e1), norm_inf (e2)), min_norm); } the example code compiles without errors. Can someone point out, how this should be fixed (either on boost or CppAD side)? In general, are there requirements for a type T to cooperate with ublas matrices one should be aware of? Thank you Peter

2 3

Is master branch open for bug fixes?
by Vicente J. Botet Escriba 30 Nov '15

30 Nov '15

Hi, the calendar says that master branch is open for bug fixes, but not mail has been sent to to notify it. Could some release manager confirm that? Best, Vicente

2 2

[program_options] empty string argument
by Benedek Thaler 30 Nov '15

30 Nov '15

Hi, I have the exact same problem: http://boost.2283326.n4.nabble.com/ProgramOptions-explicit-empty-string-arg… --compression '' gave me a specified, empty compression switch value, as expected, on boost 1.58. However, on 1.59, the empty string counts against the positional arguments, and causes regressions. Also, --compression='' gives: The argument for option '--compression' should follow immediately after the equal sign. What is the recommended workaround? Is it planned to be fixed/changed? Thanks, Benedek

1 0

[Boost.LLVM] Synopsis now available
by Andy Jost 29 Nov '15

29 Nov '15

I've created a new GitHub repository for this project and uploaded a synopsis of the proposed interface. I redesigned the interface, so it differs slightly from the prototype code and examples I gave before. Please take a look and provide feedback if you can! https://github.com/andyjost/Boost.LLVM/blob/master/boost_llvm.cpp -Andy

1 0

Interest in an LLVM library?
by Andy Jost 26 Nov '15

26 Nov '15

Is there interest in an LLVM library? My motivation is to simplify the dynamic creation of functions, modules, and programs by defining an EDSL modeled after the C language. LLVM provides an API based exclusively on function calls that is verbose and difficult to use. The EDSL is more expressive and easier to use. (This may remind some people of Boost.Python and indeed these libraries are similar in motivation.) The scope of this proposal is limited. The proposed library does not compile, link, optimize, save, or load anything, for example, since the LLVM API is suitable for that. Also, it may not support obscure features, even if they seem to be within its purview, since one can always make direct calls to the LLVM API. I have written about 6500 lines of prototype code in the context of another project (a compiler for the language Curry, if anyone is interested). It is not a complete solution, but is by no means trivial, either. I'll discuss that next, but since the discussion is somewhat lengthy, let me first explain what I'm looking for by sending this. I think this EDSL would make a good Boost library. If others agree, then the next step is to review the design. I need second opinions and help from more knowledgeable people to improve the design. There are a few places in particular where I think a redesign is necessary. After that, I'm happy to implement the final library (and would gladly accept help, if anyone is interested). Now, I'll show a few examples and provide links to the prototype code. First, here's how to create a module and put it in scope: module const example_module("example"); scope _ = example_module; The scope object sets the insertion point for types, functions, and global variables. We can create a type as follows: type i32 = int_(32); i32 is a 32-bit integer. It is easy to build more complex types, e.g., i32[2] is an array type, *i32 is a pointer type, and i32(i32,i32) is a function type. An expression like i32(42) produces a constexpr. As you might guess at this point, the prototype makes heavy use of SFINAE. I've gone to a lot of effort to make this work with everything I can think of, particularly multi-dimensional arrays and initializer_lists. So, an expression like (i32[3][2])({{1,2,3},{4,5,6}}) works! (Note: i32[3][2] is the C++ type int32_t[2][3] because that's the only sensible way to interpret successive calls to operator[]). We can create a struct from a sequence of types like this: type foo = struct_("foo", {i32, *i32}); Or, we can leave out the sequence to get an opaque struct. A function prototype can be created as follows: function const f = extern_(i32(i32), "f", {"i"}); This function, f, takes an i32 (named "i") and returns an i32. The function is placed in example_module, since the code appears in its scope. There are two other linkage-specifying functions: static_ and inline_. extern_ and static_ are also used to create global variables (i.e., if the type is not a function). To define the body, we create another scope: { scope _ = f; // code for f. } To understand this, we have to discuss scopes in more depth. There are three nested levels of scope: the current module, the current function, and the current basic block. The code above sets the current function to f and the current basic block to f's entry point. Generally speaking, within a function body we write statements that generate instructions. Those instructions are inserted into the current function at the end of the current basic block. To define the body, we can declare values and operate on them. For example: value i = arg("i"); Here, "arg" is a special function that fetches the named function parameter. We can add instructions to f using operators or special methods. For example: value j = i + 1; return_(j); Branches manipulate the current basic block. Here's an if statement: label true_path, false_path; if_(i, true_path, false_path); { scope _ = true_path; // code for true. } /* else */ { scope _ = false_path; // code for false. } // new basic block here. This generates instructions to test i, take the appropriate branch, and then continue to a new basic block in the right places (which depends on whether the paths terminate with a branch instruction). It also updates the scope so that statements following if_() are inserted into the new basic block. Believe me when I say it is not trivial to do this with the LLVM API. Although it is sometimes necessary to pre-declare labels as shown above, we can usually employ C++11 lambdas to simplify the encoding: if_(i , []{ /* code for true */} , []{ /* code for false */ } ); The prototype code can be found under https://github.com/andyjost/Sprite-3/tree/master/include/sprite/backend. Also, there are many examples under https://github.com/andyjost/Sprite-3/tree/master/examples. Other parts of the Sprite-3 project are unrelated to this proposal. A good example to start with generates the Fibonacci numbers (https://github.com/andyjost/Sprite-3/blob/master/examples/fib.cpp) Here's the interesting part: // Create a new module and associate it with this lexical scope. module const fib_module("fib"); scope _ = fib_module; // Declare types. auto const char_ = types::char_(); auto const i32 = types::int_(32); auto const i64 = types::int_(64); // Declare external functions. auto const printf = extern_(i32(*char_, dots), "printf"); // Define the @fib function. auto const fib = extern_(i64(i64), "fib", {"n"}); { scope _ = fib; value n = arg("n"); if_(n <(signed_) (2), []{return_(1);}); return_(fib(n-2) + fib(n-1)); } // Define the @main function. auto const main = extern_(i32(), "main"); { scope _ = main; value const x = fib(5); printf("fib(5)=%d\n", x); return_(0); } After this code runs, fib_module contains an intermediate representation of the program. The LLVM API can be used to save that to disk, compile it to assembly, link in the C library (to get printf), or JIT compile any of the functions, among other things. Thanks to everyone who made it this far :) I'm looking forward to your feedback. -Andy

9 21

[trippels-ppc64le][math] Missing quadmath.h errors
by Andrey Semashev 24 Nov '15

24 Nov '15

Hi, I'm seeing some test failures on the trippels-powerpc64le-gcc-6.0 tester that amount to Boost.Math failing to build because the quadmath.h header is missing. http://www.boost.org/development/tests/develop/developer/output/trippels-po… I understand that gcc 6.0 is an unreleased compiler, but the error is probably not a consequence of a compiler bug. Besides, another tester, Flast-FreeBSD10-gcc-6.0.0~gnu++11, passes. Is it possible that the header is not provided for powerpc64le? Or is an optional dependency whose presence is misdetected? Is this a known problem?

3 5

[teeks99][test] Test failures on MSVC 8-11
by Andrey Semashev 23 Nov '15

23 Nov '15

Hi, I'm seeing massive Boost.Log test failures on teeks99 with MSVC versions 8 through 11. The links to the failure messages lead to Boost.Test but the console output is not helpful (shows a successful compilation of a source file [1]). I can see Boost.Test tests are also failing massively on these compilers. Could this be fixed? [1]: http://www.boost.org/development/tests/develop/developer/output/ teeks99-08d-win2012R2-64on64-boost-bin-v2-libs-log-test-attr_attribute_set- test-msvc-11-0-dbg-adrs-mdl-64-thrd-mlt.html

6 18

[Config] boost::uint32_t != std::uint32_t on some targets
by Louis Dionne 23 Nov '15

23 Nov '15

Dear Boost, I recently fell into a trap where a program wouldn't compile because of a difference between `boost::uint32_t` and `std::uint32_t`. Specifically, I was trying to cross-compile from OS X to ARM, and the following program wouldn't compile #include <boost/cstdint.hpp> #include <cstdint> #include <type_traits> static_assert(std::is_same<std::uint32_t, boost::uint32_t>::value, ""); int main() { } I was building with arm-none-eabi-g++ -I /path/to/boost -std=c++11 -c main.cpp I have asked a question on StackOverflow [1], and I now understand why the two types are not required to be the same. However, I think it is a QOI issue that those two types are not the same, since it makes interoperating between `std::uint32_t` and `boost::uin32_t` more difficult. Is there a reason for this difference, and if not would it be reasonable to ensure that `boost::uint32_t == std::uint32_t` whenever the latter is defined, i.e. in C++11 and above? Regards, Louis [1]: http://stackoverflow.com/q/33857554/627587

3 2

build and install boost subset does not install the header files
by George Georgiev 22 Nov '15

22 Nov '15

Hi, I am trying to use github boost to obtain a subset of the libraries. I found that using the following subset of modules allows me to build boost_system. git submodule update --init tools/build || exit 1 git submodule update --init tools/inspect || exit 1 git submodule update --init libs/assert || exit 1 git submodule update --init libs/config || exit 1 git submodule update --init libs/core || exit 1 git submodule update --init libs/predef || exit 1 git submodule update --init libs/system || exit 1 git submodule update --init libs/utility || exit 1 The problem is that ./b2 ... install does not copy the header files. Is this a bug that I am hitting? My commands are: ./bootstrap.sh --prefix=../../boost --includedir=../../boost/include || exit 1 PATH=$CLANGBIN:$PATH \ ./b2 \ toolset=clang \ cxxflags="-std=c++11 -stdlib=libc++ -isystem/Developer/SDKs/MacOSX10.7.sdk/usr/include" \ linkflags="-stdlib=libc++" \ install threading=multi link=static Thanks, -g

2 3

[type_traits] Is_nothrow_move_constructible fails on mngw
by Andrzej Krzemienski 21 Nov '15

21 Nov '15

Hi, It looks like is_nothrow_move_constructible (in branch develop, on testers igaztanaga-gcc-4.6c++11 and igaztanaga-gcc-4.7c++11) fails the compilation rather than returning a true-false answer. <http://www.boost.org/development/tests/develop/igaztanaga-gcc-4-7c++11.html>I filed a ticket for it: https://svn.boost.org/trac/boost/ticket/11811 Reards, &rzej

1 0

[thread] Boost threading on VMware ESXi
by Fu ji 20 Nov '15

20 Nov '15

Hello, Is there anyone who try to use boost threading on ESXi (posix like system from VMware) or try to port it? Best regards, Damian

1 0

Re: [boost] boost log memory leak? Maybe it is my wrong.
by Jefferyliangmh 16 Nov '15

16 Nov '15

Many thanks andrey.semashev's reply. I send my demo application codes in BoostDemo.rar file. "logger" is my wrapped module by win32 dll. "BoostDemo" is my MFC test application, call logger code written in CMainFrame::CMainFrame() fuction, like this : AppLogger::log("this is test message"). Memory leak display in output windows when compiled BoostDemo application. 2015-11-16 2015-11-16 Jefferyliangmh 发件人：boost-request(a)lists.boost.org 发送时间：2015-11-16 01:00 主题：Boost Digest, Vol 4908, Issue 1 收件人："boost"<boost(a)lists.boost.org> 抄送： Send Boost mailing list submissions to boost(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.boost.org/mailman/listinfo.cgi/boost or, via email, send a message with subject or body 'help' to boost-request(a)lists.boost.org You can reach the person managing the list at boost-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost digest..." The boost archives may be found at: http://lists.boost.org/Archives/boost/ Today's Topics: 1. boost log memory leak? Maybe it is my wrong. (=?UTF-8?B?5qKB5piO6L6J?=) 2. Re: boost log memory leak? Maybe it is my wrong. (Andrey Semashev) 3. Re: checking __INTEL_COMPILER == 9999 (Blower, Melanie) 4. Re: checking __INTEL_COMPILER == 9999 (Edward Diener) ---------------------------------------------------------------------- Message: 1 Date: Sat, 14 Nov 2015 19:31:28 +0800 From: "=?UTF-8?B?5qKB5piO6L6J?="<liang_mh(a)163.com> To: "boost"<boost(a)lists.boost.org> Subject: [boost] boost log memory leak? Maybe it is my wrong. Message-ID: <220730f2.126658.15105c3ab0c.Coremail.liang_mh(a)163.com> Content-Type: text/plain; charset="UTF-8" Way I want to use win32 dynamic link library encapsulates the boost.log, the wrapper DLL in MFC MSVC 2015 calls, memory leak in output window prompt; The same library in a console program calls, no such problems. I am very depressed. Who can help me? 2015-11-14 ??? ------------------------------ Message: 2 Date: Sun, 15 Nov 2015 00:05:28 +0300 From: Andrey Semashev <andrey.semashev(a)gmail.com> To: "boost(a)lists.boost.org" <boost(a)lists.boost.org> Subject: Re: [boost] boost log memory leak? Maybe it is my wrong. Message-ID: <CAEhD+6BH=Lnw1ghLwOVarXbYGDBqoNygzcWnML+TtU7mVbB1zQ(a)mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Sat, Nov 14, 2015 at 2:31 PM, ??? <liang_mh(a)163.com> wrote: > Way I want to use win32 dynamic link library encapsulates the boost.log, the wrapper DLL in MFC MSVC 2015 calls, memory leak in output window prompt; The same library in a console program calls, no such problems. > I am very depressed. Who can help me? If you work with Boost.Log the same way in both cases then it's likely a problem in your code and not the library. Otherwise I can't help without a minimal working code sample. ------------------------------ Message: 3 Date: Sun, 15 Nov 2015 13:05:27 +0000 From: "Blower, Melanie" <melanie.blower(a)intel.com> To: "boost(a)lists.boost.org" <boost(a)lists.boost.org> Subject: Re: [boost] checking __INTEL_COMPILER == 9999 Message-ID: <B3584E72CFEBED439A3ECA9BCE67A4EF40258FCC(a)fmsmsx116.amr.corp.intel.com> Content-Type: text/plain; charset="us-ascii" Thanks for all your suggestions and replies, I will work it on the Intel side. To Edward, at the bottom of my first message there's info about one of the failure modes. --Melanie ------------------------------ Message: 4 Date: Sun, 15 Nov 2015 10:43:25 -0500 From: Edward Diener <eldiener(a)tropicsoft.com> To: boost(a)lists.boost.org Subject: Re: [boost] checking __INTEL_COMPILER == 9999 Message-ID: <n2a971$msb$1(a)ger.gmane.org> Content-Type: text/plain; charset=windows-1252; format=flowed On 11/15/2015 8:05 AM, Blower, Melanie wrote: > Thanks for all your suggestions and replies, I will work it on the Intel side. To Edward, at the bottom of my first message there's info about one of the failure modes. Thanks, I see that now. ------------------------------ Subject: Digest Footer _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost ------------------------------ End of Boost Digest, Vol 4908, Issue 1 **************************************

1 0

checking __INTEL_COMPILER == 9999
by Blower, Melanie 15 Nov '15

15 Nov '15

A few years ago, circa 2010, the Intel 12.x compiler was released without having a correct value for the macro __INTEL_COMPILER. It was released using the development-only version number 9999 instead of the correct value 12xx. Later on, an Intel 12.x compiler was updated to remove this problem and the version number made correct. Meanwhile, since boost needed to add some workarounds, there was code added in a couple of boost files to check for version 9999. The check for 9999 in boost causes trouble in our current development compiler in-house testing. Is it possible to have this version checking removed from the boost sources? There's no advantage to boost users, and possibly a disadvantage if someone is still using a not-updated 12.x compiler. But hopefully that is unlikely, we're currently shipping our 16.x compiler. Here's the diff, diff --git a/include/boost/config/compiler/intel.hpp b/include/boost/config/compiler/intel.hpp index 7789b94..bbbf876 100644 --- a/include/boost/config/compiler/intel.hpp +++ b/include/boost/config/compiler/intel.hpp @@ -47,11 +47,7 @@ #undef BOOST_COMPILER #if defined(__INTEL_COMPILER) -#if __INTEL_COMPILER == 9999 -# define BOOST_INTEL_CXX_VERSION 1200 // Intel bug in 12.1. -#else # define BOOST_INTEL_CXX_VERSION __INTEL_COMPILER -#endif #elif defined(__ICL) # define BOOST_INTEL_CXX_VERSION __ICL #elif defined(__ICC) @@ -93,11 +89,7 @@ #include "boost/config/compiler/common_edg.hpp" #if defined(__INTEL_COMPILER) -#if __INTEL_COMPILER == 9999 -# define BOOST_INTEL_CXX_VERSION 1200 // Intel bug in 12.1. -#else # define BOOST_INTEL_CXX_VERSION __INTEL_COMPILER -#endif #elif defined(__ICL) # define BOOST_INTEL_CXX_VERSION __ICL #elif defined(__ICC) @@ -289,7 +281,7 @@ template<> struct assert_intrinsic_wchar_t<unsigned short> {}; // (Niels Dekker, LKEB, May 2010) // Apparently Intel 12.1 (compiler version number 9999 !!) has the same issue (compiler regression). #if defined(__INTEL_COMPILER) -# if (__INTEL_COMPILER <= 1110) || (__INTEL_COMPILER == 9999) || (defined(_WIN32) && (__INTEL_COMPILER < 1600)) +# if (__INTEL_COMPILER <= 1110) || (__INTEL_COMPILER == 1210) || (defined(_WIN32) && (__INTEL_COMPILER < 1600)) # define BOOST_NO_COMPLETE_VALUE_INITIALIZATION # endif #endif Here's the other checking for 9999 that I found. Not known to cause a problem. diff --git a/include/boost/regex/v4/regex_format.hpp b/include/boost/regex/v4/regex_format.hpp index e9006a7..bf2e552 100644 --- a/include/boost/regex/v4/regex_format.hpp +++ b/include/boost/regex/v4/regex_format.hpp @@ -180,7 +180,7 @@ private: } inline int toi(ForwardIter& i, ForwardIter j, int base) { -#if defined(_MSC_VER) && defined(__INTEL_COMPILER) && ((__INTEL_COMPILER == 9999) || (__INTEL_COMPILER == 1210)) +#if defined(_MSC_VER) && defined(__INTEL_COMPILER) && (__INTEL_COMPILER == 1210) // Workaround for Intel support issue #656654. // See also https://svn.boost.org/trac/boost/ticket/6359 return toi(i, j, base, mpl::false_()); The intel.hpp check for 9999 causes this problem, among others, float128 tests from (boost_multiprecision suite) fail due to workaround in intel.hpp fo 12.1 compiler that was released with __INTEL_COMPILER == 9999 Fails like this: $ "icpc" -c -xc++ -O0 -w1 -inline-level=0 -fPIC -m64 -DBOOST_ALL_NO_LIB=1 -DSLOW_COMPILER -DTEST_FLOAT128 -I"../../.." -I"../include" -c -o "../../../bin.v2/libs/multiprecision/test/test_tanh_float128.test/intl-lnx/dbg/dbg-symbl-\ off/test_tanh.o" "test_tanh.cpp" In file included from test_tanh.cpp(53): ../../../boost/multiprecision/float128.hpp(48): error: identifier "_Quad" is undefined typedef _Quad float128_type; ^ Thanks and regards, Melanie Blower

5 6

boost log memory leak? Maybe it is my wrong.
by 梁明辉 14 Nov '15

14 Nov '15

Way I want to use win32 dynamic link library encapsulates the boost.log, the wrapper DLL in MFC MSVC 2015 calls, memory leak in output window prompt; The same library in a console program calls, no such problems. I am very depressed. Who can help me? 2015-11-14 梁明辉

2 1

Boost 1.60.0 beta 1 Release Candidate 3 available for testing
by Marshall Clow 14 Nov '15

14 Nov '15

Release candidate files for 1.60.0 beta 3 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. Changes since rc1: * Boost.Sprit has been updated and Boost.Log now builds. * Boost.Math has been updated and now builds. [ Note: The RC2 files that I posted yesterday were incorrectly produced. RC3 is identical to what RC2 should have been -- end note ] Known issues: * Errors when building libraries for visual studio: test and type_erasure. * Boost.Test fails when building on Darwin with gcc 4.9.2 The files (and associated md5s) are: MD5 (boost_1_60_0_b1_rc3.7z) = cfac18348700d0e6c1a0e4418a57e9aa MD5 (boost_1_60_0_b1_rc3.tar.bz2) = d3cb5a59e5b38555096814a6bfbcb441 MD5 (boost_1_60_0_b1_rc3.tar.gz) = db9b011547b8933454d0dfe31f7b8551 MD5 (boost_1_60_0_b1_rc3.zip) = 216c7cd0c15c096ece24d2649a272b51 Thanks! -- The release managers

3 4

Seeking advice regarding inline namespaces
by Louis Dionne 13 Nov '15

13 Nov '15

Dear community, I am seeking advice regarding the usage of inline namespaces for header-only metaprogramming libraries. I was at Eric Niebler's talk on C++11 library design back in 2014, and I understand the problem that inline namespaces solve. I also read all of this past thread [1] on the mailing list, but did not find what I was looking for. I also understand how they can be useful for a normal header-only library __that would provide guarantees about ABI compatibility__. Indeed, if the ABI of the library changes from v1 to v2, then any client C1 exposing types from v1 in its interface and trying to link with a client C2 built against v2 will get a clean link-time error instead of a runtime error. Now, my question has several aspects: (1) How can you guarantee ABI compatibility from one version of a library to the next? IIUC, ABI can be broken by merely changing the size or the layout of a type, so guaranteeing backwards ABI compatibility means freezing those things in time, right? (2) Assuming that it is unreasonable for a library L to guarantee ABI compatibility from one version to the next, would there still be a reason to use inline namespaces to version that library? (3) When using inline namespaces to version a library (at all, not necessarily for header only libraries), are there other guidelines to follow? For example, I see that Eric Niebler's range-v3 library is all stuffed in the range/v3 subdirectory. IIUC, this would allow an eventual range-v4 library to cohabit with the range-v3 library, because people explicitly state which version of the library they're including. Is this the reason behind the v3 subdirectory? Any answer or pointer to answers is appreciated. Regards, Louis [1]: http://boost.2283326.n4.nabble.com/type-traits-general-Best-practice-for-in… -- View this message in context: http://boost.2283326.n4.nabble.com/Seeking-advice-regarding-inline-namespac… Sent from the Boost - Dev mailing list archive at Nabble.com.

2 6

Boost 1.60.0 beta 1 Release Candidates available for testing
by Marshall Clow 12 Nov '15

12 Nov '15

Release candidate files for 1.60.0 beta 1 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. IMPORTANT NOTE: The files (and associated md5s) are: MD5 (boost_1_60_0_b1_rc1.7z) = ac6b2128d951ad688421fde2d878c2a7 MD5 (boost_1_60_0_b1_rc1.tar.bz2) = 2fc232f255f1ce8868315da207c05b6b MD5 (boost_1_60_0_b1_rc1.tar.gz) = d594e10f2761abaf957a67c6a223d2a4 MD5 (boost_1_60_0_b1_rc1.zip) = 16a2d512fca7995d5fa421d13f841b0f Thanks! -- The release managers

23 49

[property_tree iostreams smart_ptr] Warning fixes
by Joachim Faulhaber 11 Nov '15

11 Nov '15

Dear all, I have submitted pull requests for mostly warning fixes. 3 of them are still open. https://github.com/boostorg/property_tree/pull/15/files https://github.com/boostorg/iostreams/pull/19 https://github.com/boostorg/smart_ptr/pull/18 Could someone merge them in, so we have this fixed for 1.60. That would be nice. Thanx in advance Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

1 0

Re: [boost] [Boost-users] Boost 1.60.0 beta 1 Release Candidates available for testing
by Tom Kent 10 Nov '15

10 Nov '15

On Tue, Nov 10, 2015 at 12:05 AM, Raffi Enficiaud < raffi.enficiaud(a)mines-paris.org> wrote: > Le 10/11/15 00:05, Tom Kent a écrit : > >> On Mon, Nov 9, 2015 at 9:52 AM, Marshall Clow <mclow.lists(a)gmail.com >> <mailto:mclow.lists@gmail.com>> wrote: >> >> Release candidate files for 1.60.0 beta 1 are available at >> http://boost.cowic.de/rc/ >> >> As always, the release managers would appreciate it if you download >> the candidate of your choice and give building it a try. Please report >> both success and failure, and anything else that is noteworthy. >> >> >> Errors when building libraries for visual studio: test and type_erasure. >> I've grabbed the repeated outputs and posted below. Full logs are at: >> >> 32-Bit: https://gist.github.com/teeks99/bed0ef4204d24677fa4e >> 64-Bit: https://gist.github.com/teeks99/6d0358817ddfe43724f7 >> >> Tom >> > > I have a fix for MSVC but some problems have also been reported for gcc4.4 > c++0x mode. I can merge the fix for MSVC to develop and/or master once > reopened. > > Raffi > Since it is preventing building of the release binaries, I think this should be merged before the beta is released. Tom

3 4

[1.60][spirit] Unmerged changes prevent compilation
by Andrey Semashev 10 Nov '15

10 Nov '15

Hi, The latest 1.60 beta RC fails to build Boost.Log because some changes in Boost.Spirit has not been merged to master. At least these patches need to be merged to master: 1. Fix the duplicate definition of strip_single_element_vector specialization: https://github.com/boostorg/spirit/commit/4d8899fdfe26237d6d983a7ac5528d00f… 2. Fix an attempt to construct an instance of none_t: https://github.com/boostorg/spirit/commit/534cf39f15ced047359ee8b6dfe434635… 3. Although it's not strictly a build breaker, this change fixes a bunch of warnings about signed/unsigned mismatch: https://github.com/boostorg/spirit/pull/140 After applying those patches to the RC Boost.Log builds successfully. These commits and the PR has been in develop for quite some time, could someone merge them to master, please?

4 7

[Range] sorted and randomized adaptors
by Mohammed El-Afifi 10 Nov '15

10 Nov '15

Hello everybody, I know this might have been raised a few times before in this mailing list, but I'd like to know if it's possible(or otherwise what would prevent) to have sorted and randomized adaptors so that I may have a sorted and randomized view of a range respectively. Something like vector<int> x; // operations to fill x x | boost::adaptors::sorted; x | boost::adaptors::randomized;// That one might also take an optional random generator as a parameter. I understand that in this case the adaptor isn't entirely lazy as the adapted(x here) must be completely consumed before producing a single element in the resulting range. I want to know however if having such adaptors may contradict any basic principles of the existing adaptors. P.S. Two other threads I found that discussed the same idea(for sorted only): - http://lists.boost.org/Archives/boost/2009/03/149247.php - http://lists.boost.org/Archives/boost/2006/05/105122.php

3 2

Seeking feedback on SegmentedTreeSeq (sequence data structure with efficient random access insert and erase)
by Chris Clearwater 09 Nov '15

09 Nov '15

Greetings, At this time I would like to solicit feedback for my library SegmentedTreeSeq. It is an implementation of a counted B+Tree that allows efficient random access insert and erase. It's an ideal data structure for an application such as a text editor. I am also seeking interested reviewers as I feel it has reached a state that is ready for formal review. Features: - Implements the union of std::vector, std::deque, and std::list interfaces. - Implements the C++11 allocator model. - Implements the full C++14 interfaces including emplacement and move semantics. - O(log n) to obtain an iterator at any position. - O(log n) insert and erase. - Amortized O(log n) iterator movement. - Strong exception guarantee for insert. - Support for incomplete types. - SCARY iterators. - Best in class performance for many operations. - Low memory overhead for data of any type. Links: - Incubator: http://rrsd.com/blincubator.com/bi_library/segmentedtreeseq-2/?gform_post_i… - Repository: https://github.com/det/segmented_tree_seq - Documentation: https://det.github.io/segmented_tree_seq Thanks, Chris

2 2

[1.60.0] Release Notes
by Daniel James 08 Nov '15

08 Nov '15

Hello everyone, If you haven't done so already, please can you add your entries to the release notes. Easiest way to do so is to create a pull request by clicking on the pencil icon at the top right of the source code at: https://github.com/boostorg/website/blob/master/feed/history/boost_1_60_0.q… Or if you prefer you can email me. thanks, Daniel

2 1

[regression] Test results unavailable
by Andrey Semashev 07 Nov '15

07 Nov '15

Hi, Is anyone able to see develop test results? I'm seeing a blank page.

3 4

[build] How do I build for windows phone?
by John Maddock 06 Nov '15

06 Nov '15

Boost.Build evidently has options for building for windows store and windows phone. The store builds work fine for me, but the phone builds fail as there is no compiler on the command line generated: ../../../bjam config_info msvc-14.0 windows-api=phone -d2 ...found 179 targets... ...updating 5 targets... file ..\..\..\bin.v2\libs\config\test\config_info.test\msvc-14.0\debug\link-static\runtime-link-static\windows-api-phone\config_info.obj.rsp "config_info.cpp" -Fo"..\..\..\bin.v2\libs\config\test\config_info.test\msvc-14.0\debug\link-static\runtime-link-static\windows-api-phone\config_info.obj" -TP /Z7 /Od /Ob0 /W3 /GR /Zc:forScope /Zc:wchar_t /MTd /wd4675 /EHs -c -DBOOST_ALL_NO_LIB=1 -DWINAPI_FAMILY=WINAPI_FAMILY_PHONE_APP -D_WIN32_WINNT=0x0602 "-I..\..\.." compile-c-c++ ..\..\..\bin.v2\libs\config\test\config_info.test\msvc-14.0\debug\link-static\runtime-link-static\windows-api-phone\config_info.obj /Zm800 -nologo @"..\..\..\bin.v2\libs\config\test\config_info.test\msvc-14.0\debug\link-static\runtime-link-static\windows-api-phone\config_info.obj.rsp" '/Zm800' is not recognized as an internal or external command, operable program or batch file. Any ideas what I'm doing wrong? BTW I can't find any docs mentioning these options - and it's something end users building Boost may well need? Finally a supplementary question: has anyone succeeded in running regression tests on either the store or phone platforms? If I run: /bjam config_info msvc-14.0 windows-api=store I get: testing.capture-output ..\..\..\bin.v2\libs\config\test\config_info.test\msvc-14.0\debug\link-static\runtime-link-static\windows-api-store\config_info.run ====== BEGIN OUTPUT ====== Access is denied. EXIT STATUS: 5 Along with a screen message saying the app can't be run on my PC. Any ideas? Many thanks, John.

3 4

[thread] boost::future::then
by Vladimir Prus 06 Nov '15

06 Nov '15

Hi, looking through docs for some other futures implementation [1], I see this: Why not use boost::future? # At the time of writing, 1.53 (the first version with the requisite features) was brand new, not well-tested, and not available to [...] developers. It is still a bit buggy/bleeding-edge They haven't fleshed out the threading model very well yet, e.g. every single then currently spawns a new thread unless you explicitly ask it to work on this thread only, and executor support was nonexistent (and now, is still experimental). Now, 1.53 is ancient. Can anybody comment on these statements regarding boost::future::thread state in 1.59? In particular, suppose I have this: // Thread 1 boost::promise<int> pi; boost::future<int> fi = pi.get_future(); // pass pi to thread 2 somehow fi.then(....); // Thread 2 pi.set_value(100); And I want continuation to be executed in thread 1, assuming that thread 1 runs Qt event loop, allowing me to use QTimer::singleShot, or queued signal, or similar mechanism. How would I go about making boost::future do it? Has anybody done so? Thanks, Volodya

4 41

The release branch will close tonight for the 1.60 beta
by Marshall Clow 05 Nov '15

05 Nov '15

Please do not merge to the release branch after tonight until the 1.60 beta is released (scheduled for next Wednesday) unless you have specific approval from the release managers. Thank you. (There will be a chance to merge bug fixes and documentation updates after the beta) -- Marshall (and the rest of the release managers)

2 2

[config] macro for portable restrict and restrict references
by Joel FALCOU 04 Nov '15

04 Nov '15

I pushed a PR that adds the macro BOOST_RESTRICT to take place of the compielr specific __restrcict/__restrict__ keyword. It also comes with an indicator if said keyword can be applied to references. https://github.com/boostorg/config/pull/81 Comments welcome.

1 0

[String Algo] Any reason the predicates don't optimize for random access iterators?
by Nevin Liber 04 Nov '15

04 Nov '15

I was looking in boost/algorithm/string/predicate.hpp and noticed that that the predicates *starts_with, *ends_with, *contains and *equals don't optimize for random access iterators. While I haven't done any benchmarks yet, it seems like it would be faster for random access iterators to do an O(1) length check at the beginning and then while looping only check one iterator against its end instead of two. Thoughts? Nevin :-) -- Nevin ":-)" Liber <mailto:nevin@c <nevin(a)eviloverlord.com>plusplusguy.com> (847) 691-1404

2 1

[test][serialization] Fwd: [Boost-testing] regression testing failure on develop branch
by Rene Rivera 03 Nov '15

03 Nov '15

---------- Forwarded message ---------- From: Aparna Kumta <aparna.kumta(a)oracle.com> Date: Mon, Nov 2, 2015 at 2:42 PM Subject: [Boost-testing] regression testing failure on develop branch To: Running Boost regression tests <boost-testing(a)lists.boost.org> My regresion tests are failing on develop branch as follows: error: at /export/home/boost_regression_develop/boost_sparc-S2_stlport4/boost_bb/src/kernel/modules.jam:107 error: Unable to find file or target named error: 'test_boost_array.cpp' error: referred to from project at error: '../libs/serialization/test' Anyone seeing this issue? Thanks, Aparna _______________________________________________ Boost-Testing mailing list Boost-Testing(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-testing -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

4 3

Interest in a Boost.Chrono/Date library
by Vicente J. Botet Escriba 03 Nov '15

03 Nov '15

Hi, maybe some of you have already see the Howard Hinnant presentation at CppCOn2015 [1] about his new data-v2 library [2]. My prototype of Boost.Chrono/Date library ([3] ] was based on the Howard original library, but when we want to reach the maximum of performances we need to use a specific date class for each usage. This is what Howard explains in his marvelous presentation ans his tiny date library My post here wants to know if there is interest in a library providing what H.H. date library provides in Boost. Note that his data-v2 library yet doesn't provides as much as Boost.Date provides but IMHO it is much elegant and efficient. If there is enough interest, I will request you to do a first review of the H.H. Date-V2 library. Then once we have a consensus I will make my POC Chrono/Date library ready for review. H.H. Date-V2 is under MIT license, which IIRC is compatible with the Boost license. I don't know yet if would need to add this license, as my POC [3] is already a good starting point, nevertheless, I would like to know if there could be any issues about having the source under both licenses. Best, Vicente [1] https://www.youtube.com/watch?v=tzyGjOm8AKo [2] https://github.com/HowardHinnant/date [3] https://github.com/viboes/chrono_date/commits/master First commit Nov/2011 Last-Mars2014

8 17

Math tools polynomial enhancements
by Jeremy Murphy 02 Nov '15

02 Nov '15

I was just looking at the polynomial class and thinking that it could be enhanced substantially with more operators. Presumably with division and remainder it would be a Euclidean ring and then you could even call gcd on it. I have a draft implementation ready but I wanted to check that there is interest from the maintainers. Cheers. Jeremy

9 27

[base_from_member][sun-next_cpp11] problem with variadics at base_from_member
by Joaquín M López Muñoz 02 Nov '15

02 Nov '15

Hi, In 2012, boost::base_from_member was equipped with variadics machinery to perfect-forward construction arguments to the contained member. Unfortunately, Solaris Studio 12.5 on Intel chokes on it (http://tinyurl.com/no7trgb ): "../boost/utility/base_from_member.hpp", line 137: Error: Parameter pack 'x' not expanded with '...' [...] Oddly enough, the same compiler does work fine on Sparc. May I suggest that lines 129-132 of boost/utility/base_from_member.hpp #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \ !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \ !defined(BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS) && \ !(defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 4)) be added a special provision for this environment (the same way it already has for GCC 4 and prior)? #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \ !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \ !defined(BOOST_NO_CXX11_FUNCTION_TEMPLATE_DEFAULT_ARGS) && \ !(defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 4)) && \ !(defined(__SUNPRO_CC) && defined(__i386) && (__SUNPRO_CC <= 0x5140)) I can't unfortunately test this myself as I don't have access to the compiler. FWIW, my interest in having this fixed is that it's seemingly the only bug preventing Oracle Solaris Studio 12.5 on Intel from supporting Boost.MultiIndex. Joaquín M López Muñoz Telefónica

3 3

[GitHub] [PR] setting default branch to 'develop'
by Michel Morin 01 Nov '15

01 Nov '15

Hi, We sometimes forget to change the base branch of PR from 'master' to 'develop', even if we know PR should be made against 'develop' branch! To prevent from accidentally making PR against master branch, it'd be nice to **set the default branch to 'develop' branch** for Boost repositories on GitHub. (Then, the default base branch of PR would be set to 'develop' branch.) To change the default branch, it takes just a few clicks on web browser: https://help.github.com/articles/setting-the-default-branch/ Thoughts? Regards, Michel P.S. Some libraries have already done this, but most of Boost libraries don't do this yet.

10 22