July 2014 - Boost - lists.boost.org

Help about boost library x64 used in the LibLas tools
by Luca Nardelli 26 Jul '14

26 Jul '14

Helo to all, thanks a LOT for your great work! I'm trying to use the x64 library for VS 2013 (12), but I have a lot of "unresolved errors" when I try to compile the *LibLas *library that uses boost. For example I get this error: *error LNK2001: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::system_category(void)" (?system_category@system@boost@@YAAEBVerror_category@12@XZ)* Could you maybe help me or give some hint? Thanks!!! -- "Il miglior modo per cambiare e iniziare"

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C++ committee meeting report
by Beman Dawes 25 Jul '14

25 Jul '14

The C++ committee met last week in Rapperswil, Switzerland. Actions that might be of interest to Boosters include: * Shipped the File System TS for ISO DTS (i.e. final) ballot. Since it would be very unusual for at DTS ballot to fail, the File System TS is essentially done. The committee is now actively looking for File System TS 2 proposals. My work now shifts to bringing the Boost implementation into compliance. * Shipped the Library Fundamentals TS for ISO PDTS (i.e. preliminary) ballot. This TS includes Boost.Any and Boost.Optional. * Voted to start work Library Fundamentals TS 2. The plan is to issue a continuing stream of Library Fundamentals TSes, with work starting on the next TS as soon as content for the current TS freezes. Hopefully Boost developers will submit proposals for this TS too. It will be a good home for small libraries that don't need a whole TS of their own. * Shipped the C++ Extensions for Parallelism TS for ISO PDTS (i.e. preliminary) ballot. * The Library Evolution Working Group (LEWG) voted to base the Networking TS on Boost.ASIO. That was a major surprise, as a Networking Study Group had been trying to build up a Networking TS from many small proposals. But in LEWG polls, support for ASIO was overwhelming, with no one at all voting against. This was a major vote of confidence for Boost.ASIO and Chris Kohlhoff. And several ASIO supporters were not even in the room at the time because Filesystem issues were being worked on elsewhere. The next C++ committee meeting is November 3rd to 8th in Urbana-Champaign, IL, USA. As always, Boosters welcome. --Beman

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[rational] Inadvertent construction from double
by Andrzej Krzemienski 25 Jul '14

25 Jul '14

Hi, I have encountered something I consider a bug in boost::rational's interface. Its documentation discusses in detail why conversion from double is not supported, but the following code works fine: #include <iostream> #include <boost/rational.hpp> int main() { double d = 31.82; boost::rational<int> r = d; std::cout << r << std::endl; } With the following result: 31/1 It just discards the fractional part. Such conversion is really confusing an I claim should be explicitly deleted. Regards, &rzej

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Use of third-party libraries
by Michael Shepanski 25 Jul '14

25 Jul '14

On one hand, there's this: "A Boost library *should not* use libraries other than Boost or the C++ Standard Library." (http://www.boost.org/development/reuse.html) On the other hand, sometimes it just seems like common sense. E.g. Boost.Math uses NTL, MPFR, and others. Now I'm trying to get quince and its backend libraries (quince_postgresql, quince_sqlite) into shape for blincubator. The job of the backends is to liaise between quince and other people's libraries: libpq and sqlite3. There is no getting around that. So I was hoping that the prohibition would be waived in this case, as it was in the case of Boost.Math. The trouble I have is that quince_postgresql and quince_sqlite are *not* header-only, and their code that calls libpq and sqlite3 is in .cpp files. And yet I don't want them to break the boost build for people who don't need this stuff, and haven't installed either or both of those third-party libraries. Any suggestions? Any precedents? Thanks, --- Michael

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How to establish boost configurations for cross-compilers not currently covered?
by Dave Gomboc 25 Jul '14

25 Jul '14

The boost config manual (http://www.boost.org/doc/libs/1_55_0/libs/config/doc/html/index.html) does not explicitly address the case where one is attempting to determine the relative lack of C++98 compliance of a cross-compiler (e.g., for an embedded system) that is not already within Boost's supported set of compilers. Is there a clear process documented somewhere for how to go about this? If not, I would appreciate any tips. I have more than one cross-compiler that I am interesting in "Boost"ing. Thanks, Dave

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[function_types] synthesis & explicit calling convention
by Domagoj Saric 25 Jul '14

25 Jul '14

I am unable to synthesize a pointer to a function (or a function type) with the fastcall (or any other, explicitly specified) calling convention. MSVC10 SP1: ** #define BOOST_FT_COMMON_X86_CCs #include "boost/function_types/function_pointer.hpp" #include "boost/function_types/property_tags.hpp" causes error C1017: invalid integer constant expression boost\boost_1_55_0\boost\function_types\detail\pp_cc_loop\preprocessed.hpp 28 ** doing #define BOOST_FT_COMMON_X86_CCs 1 (contrary to documentation but suggested in some places) and including #include <boost/function_types/config/config.hpp> fixes the above compiler error but then the actual typedef typename boost::function_types::function_pointer < MyParameterTypeList, boost::function_types::tag<boost::function_types::non_variadic, boost::function_types::fast_cc> >::type MyFunctionPointerType; fails with error C2065: 'fast_cc' : undeclared identifier help..please? :) -- Domagoj Saric Software Architect www.LittleEndian.com

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[type_erasure] call with multiple placeholders
by Benedek Thaler 25 Jul '14

25 Jul '14

Hi, I have the following type erasure setup: https://github.com/erenon/pipeline/blob/type_erasure/include/boost/pipeline… I'd like to make `any` have a method template, `connect_to`, i.e: class any { template <typename T> auto connect_to(const T&) {} } I have a concept, added to the main concept like this: detail::has_connect_to<type_erasure::_self, type_erasure::_a> And also a concept_interface specialization. (Bottom of the file in the link above) The doc says: "When there are multiple placeholders involved, you will have to use tuple, or pass the bindings explicitly, but the substitution still works the same way. " I'm trying to do just like this, but without success. Errors include: error: ‘const struct boost::type_erasure::_self’ has no member named ‘connect_to’ error: ‘apply’ is not a member of ‘boost::pipeline::detail::has_connect_to<boost::type_erasure::_self, boost::type_erasure::_a>’ *error: no matching function for call to ‘call(boost::type_erasure::concept_interface<...[snip]...>`* I think the last one is the core issue, but I can't figure out how to pass the binding properly. I don't know why does concept_interface show up as the first argument. Thanks, Benedek

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[xpressive] capture float?
by Greg Rubino 24 Jul '14

24 Jul '14

Hi all, I'm trying to capture a float with xpressive and put it into a local map. As a simplified example, I tried just pushing the matched pattern to a float and the result is always a float containing '0'. namespace xpr = boost::xpressive; std::map<float, std::string> l_floatOperMap; xpr::sregex l_relation = xpr::as_xpr("<=") | ">=" | "<" | ">"); l_floatRestriction = !(xpr::s1 = l_relation) >> (xpr::s2 = (+xpr::_d >> '.' >> +xpr::_d)) [xpr::ref(l_floatOperMap)[xpr::as<float>(xpr::s2)] = xpr::as<std::string>(xpr::s1)]; However, when I go to print the contents of l_floatOperMap, it contains only the tuple (0, ""). Is it something I'm doing wrong? It seems like this should work to me. Thanks, Greg

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[Boost Library Incubator] Unable to submit library
by Edward Diener 22 Jul '14

22 Jul '14

I tried to submot a library to the Boost Library Incubator only to get a parsing error message followed by absolutely nothing happening no matter how many times I attempted to click the Submit button. It is no fun re-entering all that data again.

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[winrt support] Adding support for Windows 8 store/phone to Boost libraries
by stgates 22 Jul '14

22 Jul '14

Hi, I work for Microsoft and we’ve been taking a look at making a some of the libraries in Boost work in the Windows 8 store and phone 8 runtime environment (WinRT). The main issue is use of Win32 desktop APIs that are banned in WinRT. The fixes generally involve updating to a newer non-banned version, like CreateEvent to CreateEventEx, or replace areas that call banned APIs using ifdef macro techniques. Similar to what already exists in some places of Boost when targeting different platforms or operating system versions. Files which do not use any banned APIs are largely unaffected. So far we’ve made the thread, chrono, system, and date_time libraries work in WinRT. To facilitate building and testing, changes are also required to the build and test libraries. Listed at the end of this message is a summary of the major changes made. I’m unfamiliar with the process for contributing back to Boost and would like to know what is the best way to work, to contributing back these changes to each of the individual libraries? I see the documentation for working with the git submodules (https://svn.boost.org/trac/boost/wiki/StartModPatchAndPullReq) Right now the changes for each library are in a forked repository on a new branch called ‘winrt’ from the ‘develop’ branch. For example the changes we've made for the chrono library can be located here: https://github.com/MSOpenTech/chrono/tree/winrt. Is the best way to proceed, or should I to just initiate a pull request to the develop branch on each of the individual libraries? Thanks, Steve Boost Build To support deciding which Windows API to target I added a new feature <windows-api> with values desktop, store, and phone. When utilizing the Visual Studio 2012 on Windows 8 or later the store and phone options are available, otherwise desktop is the default. Most of the changes in msvc.jam are to deal with selecting the correct vcvars setup script since with phone it is in a different location. I also added ARM support to the msvc toolset. For libraries which support the new Windows Runtime they now produce both the desktop and store binaries by default. This is done by calling the supported-windows-api rule I added in toolset.msvc which is called in the default-build section of each library’s Jamfile to indicate if targeting WinRT is supported. When building for the Windows 8 store or phone a new macro is now defined BOOST_WINAPI_FAMILY, set with the same value as WINAPI_FAMILY. This is then used in the individual Boost libraries to detect if targeting the new Windows Runtime and avoid certain banned APIs. To handle running tests against WinRT in an automated fashion that integrates well into the Boost workflow of running tests as part of the build, if windows-api is set to store, the test and all its binary dependencies need to have the APPCONTAINER requirement stripped. This then allows execution outside of the sandboxed Windows store environment. To do this all dependent dlls are copied into the tests executable’s folder, if using <link>shared. This is necessary to avoid modifying the APPCONTAINER flag on the actual product binaries. Just let me know if this needs more explanation, I’ll be glad to go into more detail if necessary. With this change the tests for Windows store run just like the existing Windows tests. I also added a new feature to control whether or not test binaries are actually executed, disable-test-execution. This is used to avoid running the ARM tests when building since Visual Studio 2012 doesn’t install on ARM devices. All these changes are in testing.msvc. Chrono The GetProcessTimes and GetThreadTimes functions doesn’t exist for WinRT and there are no replacements so the thread_clock and process user, system, and cpu clock features are disabled. Only process_real_cpu_clock is supported. Thread For the thread library most of the changes are around the fact that there is no way to directly create a thread in WinRT. To work around this I implemented the boost::thread class itself on top of std::thread. This actually leads to pretty clean code, much cleaner than directly targeting the WRL thread pool like in the C runtime. Other changes include moving from TLS to FLS and basic banned API replacements like WaitForSingleObjectEx for WaitForSingleObject. In general where it makes sense updates were made to utilize new APIs on platforms when available. Test For the Boost test library I added a new macro for turning on/off debugging support (BOOST_TEST_HAS_DEBUG_SUPPORT). WinRT doesn’t support creating processes so attaching a debugger to execution like this is disabled. There also are no APIs for accessing registry keys, so this feature has been disabled as well. -- View this message in context: http://boost.2283326.n4.nabble.com/winrt-support-Adding-support-for-Windows… Sent from the Boost - Dev mailing list archive at Nabble.com.

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