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owns_lock on lock not on mutex
by gast128 13 Oct '15

13 Oct '15

Hello all, there is an owns_lock on the lock type but not on the mutex. This is quite unhandy. Any reason why? Use case is in base-derived idiom: class Foo { public: void Process() { boost::unique_lock<boost::mutex> lck(m_mtx); Update(); } protected: void Update() { ++m_n; } boost::mutex m_mtx; int m_n; }; class Bla : public Foo { public: void Process() { boost::unique_lock<boost::mutex> lck(m_mtx); Update(); } private: void Update() { assert(m_mtx.owns_lock()); ++m_n2; Foo::Update(); } int m_n2; };

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Log: [Bug] Setting attribute makes log entry disappear
by Florian Lindner 12 Oct '15

12 Oct '15

Hello, I have a tracer, that should log going in and out of a function: class Tracer { public: Tracer(Logger logger, std::string function, std::string file) : _logger(logger), _function(function), _file(file) {} ~Tracer() { using namespace boost::log; // attribute_cast<attributes::mutable_constant<int>>(core::get()->get_global_attributes()["Line"]).set(1); attribute_cast<attributes::mutable_constant<std::string>>(core::get()->get_global_attributes()["File"]).set(_file); attribute_cast<attributes::mutable_constant<std::string>>(core::get()->get_global_attributes()["Function"]).set(_function); BOOST_LOG_SEV(_logger, trivial::severity_level::trace) << "Leaving " << _function; } private: Logger _logger; std::string _function; std::string _file; }; This works fine, but as soon as I uncomment the line that sets the Line attribut I don't get any Leaving messages anymore. The attributes are added beforehand like that: using namespace boost::log; add_common_attributes(); core::get()->add_global_attribute("Scope", attributes::named_scope()); core::get()->add_global_attribute("Rank", attributes::constant<int>(5)); core::get()->add_global_attribute("Line", attributes::mutable_constant<int>(5)); core::get()->add_global_attribute("File", attributes::mutable_constant<std::string>("")); core::get()->add_global_attribute("Function", attributes::mutable_constant<std::string>("")); Setting all other attributes, similiar to Line works fine. I'm puzzled because Line does not seem to be a reserved name, it works somewhere else and the boost::log sources reveal no relevant usages of that name. What could be the problem here? I'm happy to send anyone the complate code (approx. 150 lines in total) Thanks! Florian

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Boost.Fiber mini-review report
by Nat Goodspeed 10 Oct '15

10 Oct '15

The mini-review of Boost.Fiber by Oliver Kowalke ran from Friday September 4th through Sunday September 13th. There was lively discussion, but only two actual reviews: Agustín K-ballo Bergé: not yet (list of issues below) Niall Douglas: yes, plus suggestions (below)[0] In addition I received two "review withheld" notes: Vicente J. Botet Escriba wanted me to address the previous review point by point. That seems like a reasonable request, and I apologize, but I too have time pressures. Giovanni Piero Deretta made suggestions (synopsized below) with the statement that he will make a recommendation when he sees the library author's progress along those lines. While in theory these results might seem like a hung jury, the very paucity of formal reviews supports a cautious approach. The verdict is: not yet, with specific points as noted below. No reviewer explicitly designated specific points as being essential. (Niall Douglas explicitly designated his suggestions as post-adoption enhancements.) I have made an attempt to rank the recommendations received in descending order of importance to the community. My criteria are: Robustness: does lack of this request pose significant risk to a consuming program? API stability: could this request be considered an implementation detail, or would the change break early adopters? Demand: how many people requested the same thing? If you feel that I have misrepresented the importance of one of your points (or omitted something entirely), please respond. Ultimately, of course, the importance of any given point to the community at large will be reflected in the next mini-review. ----------------------------------------------------------------- Requests: Cross-thread fiber migration: Evidently the community strongly desires the ability to transfer a suspended fiber from one thread to another.[1] Of course there must be controls. Migration might be explicit; but if implicit, there must be a way to designate which fibers may and may not be migrated. An RAII class that temporarily disables migration would also be desirable -- for instance, to guarantee TLS consistency for some specific period. Cross-thread migration support implies a requirement to document the thread safety requirements of the customization API. Standard required timing specifications: meet (30.2.4 Timing specifications [thread.req.timing]). Adapt one or more existing test suites for thread facilities to validate the correctness of the Fiber library's synchronization constructs: e.g. from libc++, libstdc++, Boost.Thread, HPX. std::chrono support: ensure that wait_until() can accept any supported time_point specialization. (The library author asserts that this has already been fixed on the 'develop' branch.) C++11 compatibility: Agustín K-ballo Bergé volunteered to help with this point post-adoption. Paul Fultz offered fit::capture to emulate C++14 move capture. Document that this_fiber::yield() (et al.) are valid from main(), or in general from a thread function, as well as from explicitly-launched fibers. Make shared_state lock requirements explicit: for example, make mark_ready_and_notify_() accept a std::unique_lock<>& (or &&) to force its caller to provide one. Avoid holding mutex during condition_variable::notify_*() calls. (The library author asserts that this has already been fixed on the 'develop' branch.) packaged_task must not decay-copy its task arguments. Align fibers::async() signature, result description and invoke_helper implementation with std::async(). Avoid returning std::move(...). Wait list implementation: try an intrusive linked list of fiber_context objects. Avoid sleeping thread when no fibers are ready -- block on external event. Better handling of waiting tasks (decentralized wait queues?). Optimization to resume awakened fiber on the thread that awakens it. Template redundancy: eliminate duplication between specializations for T, T& and void. The future, shared_future, shared_state, promise and task_object templates were specifically cited. Leverage predicate-based condition::wait() overload internally. Nested schedulers: make schedulers be schedulable entities themselves. Improve robustness of `promise' handling in Asynchronous Callbacks documentation. Avoid overconfident remarks about it. Fix Note overstating the requirements on condition_variable::wait(). The discussion also surfaced the desirability of Grand Unified Future Theory, but it was generally agreed that this is out of scope. Put differently, it would be unreasonable to put the onus on Fiber to solve that very broad cross-library problem. Many thanks to all participants, and thanks especially to Oliver Kowalke for all his work on this library! Nat Goodspeed Boost.Fiber Review Manager ________________________________ [0] Niall Douglas snuck his review recommendation into the following mail message: http://lists.boost.org/Archives/boost/2015/09/225228.php (second to final paragraph). His suggestions were in private mail. [1] Giovanni Deretta suggests that it might be possible to allocate -- without actually running -- an actual kernel thread per fiber, simply to give each fiber its own TLS area.

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boost::serialization bindings for PHP5 somewhere?
by Mauro Condarelli 10 Oct '15

10 Oct '15

Hi, I need to send some structures (and receive answers, of course) from a PHP5 front-end to a C++ back-end that already communicates with another C++ front-end via boost::serialization over a socket. Easiest would be to teach PHP5 to talk the same language. I know I can write a specific PHP5 extension in C++ and use boost::serialization there. Question is if such a beast (or something equivalent) already exists. Thanks in Advance Mauro

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serialization code compilation problem - shared_ptr_helper.cpp in Boost 1.59
by Robert Fairlie 06 Oct '15

06 Oct '15

I tried building the serialization library only using the standard b2 approach and looking at the output. It looks like shared_ptr_helper.cpp isn’t included in the build (at least for serialization). So I just left it out of my own build and my code compiled and linked OK, and my serialization seems to be working. Does this approach sound safe or am I overlooking something?

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serialization code compilation problem - shared_ptr_helper.cpp in Boost 1.59
by Robert Fairlie 06 Oct '15

06 Oct '15

Hi, I’m building the Boost serialization library in Visual Studio 2015 (for x86 and ARM) by copying the 40 or so files in libs\serialization\src and compiling them in my Visual Studio project. (I’m doing it this way because Visual Studio won’t seem to let me build everything with b2 in the ARM case). The last build of the 40 files I did used Boost 1.55 and that worked fine, but now with Boost 1.59, all files compile except shared_ptr_helper.cpp. I notice that shared_ptr_helper.cpp refers to a class called shared_ptr_helper_base, but I’ve done a full *.* search and it doesn’t seem to be declared anywhere. Also, I notice that usage of macros such as BOOST_ARCHIVE_DECL has been updated in other files, but not in shared_ptr_helper. Any advice on this would be much appreciated. Robert Fairlie

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[geometry] is there an rtree version that works with boost.1.49 and MSVC2010?
by Jeff Flinn 05 Oct '15

05 Oct '15

I pulled the version down from the old svn sandbox, but msvc2010 doesn't support the variadic template args in indexable.hpp. Any help appreciated. Thanks, Jeff

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Container features in regards to IPC
by David Schneider 04 Oct '15

04 Oct '15

Hello, I was wondering if I could suggest adding the ability to have separate allocators inside containers so that the structure (such as map) can be in a different shared memory region, or whatever, than the data. It would have variety of useful cases such as offline storage swapping out, inter-process communications, etc. This can be realized by a bit of a hack with a bunch of boiler-plate code, but I think that this could be a very useful extension over what is available in the standard library. Dave

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how to get auto_link to use shared libraries
by Jeff Archer 04 Oct '15

04 Oct '15

I am trying to use Boost 1.59.0 with Visual Studio 2015 I believe I have built correctly the shared libraries as I have the following files in stage/lib 10/03/2015 04:48 PM 968,192 boost_regex-vc140-mt-1_59.dll 10/03/2015 04:48 PM 1,100,728 boost_regex-vc140-mt-1_59.lib 10/03/2015 03:59 PM 2,561,024 boost_regex-vc140-mt-gd-1_59.dll 10/03/2015 03:59 PM 1,103,914 boost_regex-vc140-mt-gd-1_59.lib I am trying to build the credit_card_example from http://www.boost.org/doc/libs/1_59_0/libs/regex/example/snippets/credit_car… I do have several static libraries in my stage/lib. Uncertain how they got there as I thought that I had only built the debug and release shared libraries. 10/03/2015 04:52 PM 395,432 libboost_chrono-vc140-mt-1_59.lib 10/03/2015 04:02 PM 2,223,204 libboost_chrono-vc140-mt-gd-1_59.lib 10/03/2015 04:48 PM 1,416 libboost_exception-vc140-mt-1_59.lib 10/03/2015 03:59 PM 29,648 libboost_exception-vc140-mt-gd-1_59.lib 10/03/2015 04:52 PM 88,934 libboost_system-vc140-mt-1_59.lib 10/03/2015 04:02 PM 660,700 libboost_system-vc140-mt-gd-1_59.lib 10/03/2015 04:52 PM 13,542,628 libboost_test_exec_monitor-vc140-mt-1_59.lib 10/03/2015 04:02 PM 42,599,796 libboost_test_exec_monitor-vc140-mt-gd-1_59.lib 10/03/2015 04:52 PM 177,682 libboost_timer-vc140-mt-1_59.lib 10/03/2015 04:02 PM 1,319,014 libboost_timer-vc140-mt-gd-1_59.lib Compiling with BOOST_LIB_DIAGNOSTIC defined gives this output 1>------ Build started: Project: BoostRegexCreditCardExample, Configuration: Debug x64 ------ 1> BoostRegexCreditCardExample.cpp 1> Linking to lib file: libboost_regex-vc140-mt-gd-1_59.lib ========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ========== Building the project gives this error 1>------ Build started: Project: BoostRegexCreditCardExample, Configuration: Debug x64 ------ 1>LINK : fatal error LNK1104: cannot open file 'libboost_regex-vc140-mt-gd-1_59.lib' ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Precompiled headers is turned off. I believe the shared libraries are built correctly because if I rename the import library to libboost_regex-vc140-mt-gd-1_59.lib the build succeeds and the boost_regex-vc140-mt-gd-1_59.dll module is shown as loaded by the debugger and the program produces the following output. C:\Dev.ja\BoostRegexCreditCardExample\x64\Debug>BoostRegexCreditCardExample.exe validate_card_format("0000111122223333") returned 0 validate_card_format("0000 1111 2222 3333") returned 1 validate_card_format("0000-1111-2222-3333") returned 1 validate_card_format("000-1111-2222-3333") returned 0 machine_readable_card_number("0000111122223333") returned 0000111122223333 machine_readable_card_number("0000 1111 2222 3333") returned 0000111122223333 machine_readable_card_number("0000-1111-2222-3333") returned 0000111122223333 machine_readable_card_number("000-1111-2222-3333") returned 000111122223333 human_readable_card_number("0000111122223333") returned 0000-1111-2222-3333 human_readable_card_number("0000 1111 2222 3333") returned 0000-1111-2222-3333 human_readable_card_number("0000-1111-2222-3333") returned 0000-1111-2222-3333 human_readable_card_number("000-1111-2222-3333") returned 000-1111-2222-3333 Therefore, I believe I have overlooked some detail in the setup of my project. Please, can someone point out what I have failed to do correctly? Also, can/should I just delete the several libboost_...lib files from my stage/lib directory? I would prefer to always used the shared libraries. Thanks, Jeff

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problem in configuring the environment
by arto rasimus 03 Oct '15

03 Oct '15

I have Raspberry Pi, realtime kernel in it and machinekit 2.7-0 package. Boost version is 1.55-0.What to check, since the machinekit does not find the boost? (and therefore configuration script fails) Linux raspberrypi 3.18.11+ #781 PREEMPT Tue Apr 21 18:02:18 BST 2015 armv6l GNU/Linux configure: error: boost::python is required to build LinuxCNC pi@raspberrypi /machinekit/src $ dpkg -l | grep boost ii libboost-atomic1.55-dev:armhf 1.55.0+dfsg-3 armhf atomic data types, operations, and memory ordering constraints ii libboost-atomic1.55.0:armhf 1.55.0+dfsg-3 armhf atomic data types, operations, and memory ordering constraints ii libboost-chrono1.55-dev:armhf 1.55.0+dfsg-3 armhf C++ representation of time duration, time point, and clocks ii libboost-chrono1.55.0:armhf 1.55.0+dfsg-3 armhf C++ representation of time duration, time point, and clocks ii libboost-date-time1.55-dev:armhf 1.55.0+dfsg-3 armhf set of date-time libraries based on generic programming concepts ii libboost-date-time1.55.0:armhf 1.55.0+dfsg-3 armhf set of date-time libraries based on generic programming concepts ii libboost-dev:armhf 1.55.0.2 armhf Boost C++ Libraries development files (default version) ii libboost-filesystem-dev:armhf 1.55.0.2 armhf filesystem operations (portable paths, iteration over directories, etc) in C++ (default version) ii libboost-filesystem1.55-dev:armhf 1.55.0+dfsg-3 armhf filesystem operations (portable paths, iteration over directories, etc) in C++ ii libboost-filesystem1.55.0:armhf 1.55.0+dfsg-3 armhf filesystem operations (portable paths, iteration over directories, etc) in C++ ii libboost-program-options-dev:armhf 1.55.0.2 armhf program options library for C++ (default version) ii libboost-program-options1.55-dev:armhf 1.55.0+dfsg-3 armhf program options library for C++ ii libboost-program-options1.55.0:armhf 1.55.0+dfsg-3 armhf program options library for C++ ii libboost-python-dev 1.55.0.2 armhf Boost.Python Library development files (default version) ii libboost-python1.55-dev 1.55.0+dfsg-3 armhf Boost.Python Library development files ii libboost-python1.55.0 1.55.0+dfsg-3 armhf Boost.Python Library ii libboost-serialization-dev:armhf 1.55.0.2 armhf serialization library for C++ (default version) ii libboost-serialization1.55-dev:armhf 1.55.0+dfsg-3 armhf serialization library for C++ ii libboost-serialization1.55.0:armhf 1.55.0+dfsg-3 armhf serialization library for C++ ii libboost-system-dev:armhf 1.55.0.2 armhf Operating system (e.g. diagnostics support) library (default version) ii libboost-system1.55-dev:armhf 1.55.0+dfsg-3 armhf Operating system (e.g. diagnostics support) library ii libboost-system1.55.0:armhf 1.55.0+dfsg-3 armhf Operating system (e.g. diagnostics support) library ii libboost-test-dev:armhf 1.55.0.2 armhf components for writing and executing test suites (default version) ii libboost-test1.55-dev:armhf 1.55.0+dfsg-3 armhf components for writing and executing test suites ii libboost-test1.55.0:armhf 1.55.0+dfsg-3 armhf components for writing and executing test suites ii libboost-thread-dev:armhf 1.55.0.2 armhf portable C++ multi-threading (default version) ii libboost-thread1.55-dev:armhf 1.55.0+dfsg-3 armhf portable C++ multi-threading ii libboost-thread1.55.0:armhf 1.55.0+dfsg-3 armhf portable C++ multi-threading ii libboost1.55-dev:armhf 1.55.0+dfsg-3

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