February 2015 - Boost-users - lists.preview.boost.org

Boost MultiIndexContainer, how to do delayed indexing for fast insertion?
by HuMichael 17 Feb '15

17 Feb '15

I used below MultiIndexContainer typedef multi_index_container<PositionSummary*, indexed_by< ordered_unique< composite_key<PositionSummary, const_mem_fun<PositionSummary, int, &PositionSummary::positiondate>, const_mem_fun<PositionSummary, const std::string&, &PositionSummary::accountid>, const_mem_fun<PositionSummary, const std::string&, &PositionSummary::instid> > >, ordered_unique< composite_key<PositionSummary, const_mem_fun<PositionSummary, int, &PositionSummary::positiondate>, const_mem_fun<PositionSummary, const std::string&, &PositionSummary::instid>, const_mem_fun<PositionSummary, const std::string&, &PositionSummary::accountid> > > > > PositionSummaryContainer; And I inserted 10000 insts*36 accounts*100 days=36 million records //Begin testing of the multiIndexContainter std::cout << "Begin inserting data from array into the multiIndexContainter" << std::endl; timer.reset(); timer.begin(); for (int i = 0; i < numOfDays_; i++) { for (int j = 0; j < accountSize_; j++) { for (int k = 0; k < instSize_; k++) { PositionSummary* ps = psArray_[(i * accountSize_ + j) * instSize_ + k]; uniqueIndex.insert(ps); } } } printMemoryUsage(); timer.end(); std::cout << "Time take is " << timer.getInterval() << std::endl; And I found the speed of insertion is a little bit slow, about 20K+ records per second... Is there anyway to enhance this insertion speed? My data was in Oracle, properly indexed, so there should be no danger of corrupted data structure. I knew that in oracle you can first load then build index to save time, can I do the same with MultiIndexContainer, if there is a way? By the way, the parallel query speed is quite satisfactory, querying all the 36 m records on a 4 cpu(8kernal) machine takes only 2.8 seconds, code as below #pragma omp parallel for collapse(2) for (int i = 0; i < numOfDays_; i++) { for (int j = 0; j < accountSize_; j++) { const int& date = dates_[i]; const std::string& accountID = accountIDs_[j]; for (int k = 0; k < instSize_; k++) { const std::string& instID = instIDs_[i]; PositionSummaryContainer::iterator it = uniqueIndex.find(boost::make_tuple(date, accountID, instID)); if (it != uniqueIndex.end()) { #pragma omp atomic sum2 += (*it)->marketvalue(); } } //std::cout << "accountID: " << accountID << std::endl; } }

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[gsoc15] Org application closes on Friday 20th
by Niall Douglas 17 Feb '15

17 Feb '15

Three days remain until the GSoC org application closes on Friday 20th of April. As can be seen at https://svn.boost.org/trac/boost/wiki/SoC2015, we have just SIX project proposals and FIVE mentors who have publicly made themselves available on the ideas list this year. This is significantly lower than this time last year. If you would like to attract students to work on your Boost library in 2015, please consider adding a formal project idea to the list above before Friday. If you would like to mentor in some topic or field, please make yourself known to us so we can add you to the list of available mentors for 2015. Oh, and don't forget to mention the fields you are interested in! Thanks, Niall and Boris --- Boost C++ Libraries Google Summer of Code 2015 admin https://svn.boost.org/trac/boost/wiki/SoC2015

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generic vector
by U.Mutlu 17 Feb '15

17 Feb '15

Hi, I need to have a std::vector in my program, but it's type will be known only when it runs, ie. the type will be provided via a program param. The possible types are limited to these: int64_t, uint64_t, double, std::string. Is there a solution in boost or C++11 for this kind of problem? -- TIA Uenal

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[regex] problem w/ regex::extended
by U.Mutlu 16 Feb '15

16 Feb '15

Hi, the following regex expression works in perl-mode, but does not work in extented-mode. What's the reason? I think I haven't used any perl-specific construct, or did I? Where? ... #define NUM "[+-]?(\\d+\\.?\\d*|\\.\\d+)([eE][+-]?\\d+)?" #define WORD "[\\w\\-\\.~/]+" #define EQU "\\s*\\=\\s*" const string sUserRE_VarAndVal = WORD EQU NUM; #if 0 #define REGEX_ENGINE boost::regex::extended #else #define REGEX_ENGINE boost::regex::perl #endif regex reNum(sUserRE_VarAndVal, REGEX_ENGINE); ...

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[program options] option_groups.cpp example doesn't compile
by U.Mutlu 16 Feb '15

16 Feb '15

I've boost 1.55 from the debian repository. I'm trying to compile the below example of the 1.55 version (it's same as that of 1.57), but I get the following compile errors. Should I use some 'magic' compiler options, or what else is the reason for this grandious failure? $ g++ -Wall -std=gnu++11 option_groups.cpp -lboost_program_options option_groups.cpp: In function ‘int main(int, char**)’: option_groups.cpp:44:46: error: ‘class boost::program_options::typed_value<std::basic_string<char>, char>’ has no member named ‘implicit’ ("help-module", value<string>()->implicit(), ^ option_groups.cpp:96:11: error: reference to ‘exception’ is ambiguous catch(exception& e) { ^ In file included from /usr/include/c++/4.9/new:40:0, from /usr/include/c++/4.9/ext/new_allocator.h:33, from /usr/include/x86_64-linux-gnu/c++/4.9/bits/c++allocator.h:33, from /usr/include/c++/4.9/bits/allocator.h:46, from /usr/include/c++/4.9/string:41, from /usr/include/boost/program_options/errors.hpp:12, from /usr/include/boost/program_options/options_description.hpp:12, from option_groups.cpp:24: /usr/include/c++/4.9/exception:60:9: note: candidates are: class std::exception class exception ^ In file included from /usr/include/boost/throw_exception.hpp:43:0, from /usr/include/boost/any.hpp:26, from /usr/include/boost/program_options/value_semantic.hpp:12, from /usr/include/boost/program_options/options_description.hpp:13, from option_groups.cpp:24: /usr/include/boost/exception/exception.hpp:208:5: note: class boost::exception exception ^ option_groups.cpp:96:11: error: ‘exception’ does not name a type catch(exception& e) { ^ option_groups.cpp:97:17: error: ‘e’ was not declared in this scope cout << e.what() << "\n"; ^

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[context] boost::coroutines::asymmetric_coroutine<T>::pull_type iterator does not properly model InputIterator
by Mueller-Roemer, Johannes Sebastian 16 Feb '15

16 Feb '15

I’m currently on Boost 1.56 so this might have been fixed by now, but in a simple test Boost.Coroutine fails to properly model the InputIterator concept, because *it++ does not conform to the operational semantics { T tmp = *it; ++it; return tmp; } required by the standard. The failing program: #include <boost/coroutine/asymmetric_coroutine.hpp> #include <iostream> template<typename Continuation> auto foo(Continuation && yield) -> void { yield("Hello"); yield(", "); yield("World"); yield("!\n"); } //using T = char const *; using T = std::string; auto foo() -> boost::coroutines::asymmetric_coroutine<T>::pull_type { using namespace boost::coroutines; return asymmetric_coroutine<T>::pull_type{ [](asymmetric_coroutine<T>::push_type& yield) { foo(yield); } }; } auto main(int, char **) -> int { auto f = foo(); for(auto it = boost::begin(f); it != boost::end(f);) std::cout << *it++; } Which (on my machine) outputs: , World! X☺à r2 ` , ` , Ç2 Ç Failing to model the InputIterator concept is bad, because then it isn’t any kind of standards-conforming iterator at all. Interestingly, if T is char const * and not std::string the program works as expected. Is there some other subtle bug at work here? -- Johannes S. Mueller-Roemer, MSc Wiss. Mitarbeiter - Interactive Engineering Technologies (IET) Fraunhofer-Institut für Graphische Datenverarbeitung IGD Fraunhoferstr. 5 | 64283 Darmstadt | Germany Tel +49 6151 155-606 | Fax +49 6151 155-139 johannes.mueller-roemer(a)igd.fraunhofer.de | www.igd.fraunhofer.de

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Strange boost::threads behaviour
by Lorenzo Trivelli 16 Feb '15

16 Feb '15

Hi to everyone, first of all thanks to all the people who writes and manteins this wondefrul collection of libraries ;-) While analyzing a resource exaustion problem on a production machine, (Windows) I found out astrange behaviour of boost::threads regarding event object. The problem is that after a certain number of iterations it semms that the thread lib allocates an EventHandle which is never freed. I managed to reproduce in some ways the behaviour, but I'm a bit clueless about its reason. To be honest, the amount of handles "leaked" by the test code is quite less than the amount I found on production server, but test code is also quite simpler. Now some info: 1) OS: Win 2033 , Win 2008 2) I tested it with both 1.46.1 and 1.57.0, compiled using stlport using VS2005 3) if you want I can attach the sample code with a but if info on how to reproduce the behaviour thanks in advance L. Trivelli

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[future] Confused about the represents in Doc "boost::future"
by Cheng Mo 16 Feb '15

16 Feb '15

Hi all : I got confused in Doc of boost :: futures and I can't got the point of sort of terms. The represents in Overvies of Futures like " Instances can be freely copied and assigned, and boost::shared_future<R>::get() returns a non const reference so that multiple calls to boost::shared_future<R>::get() are safe." no doubt that a const reference .... are safe. a non const reference could be changed by external stimuli. isn't ? Or the key is "Instances can be freely copied" , so that we can say "are safe"? Cheer~ Martin

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[program options] examples where?
by U.Mutlu 15 Feb '15

15 Feb '15

In the online documentation tutorial there are multiple times mentioned references to the examples page. But where are these examples exactly located? On the documentation pages I couldn't find a link to the examples page. Do I need to install the complete boost developer version locally to get to the examples? -- cu Uenal

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[program options] an alternative for "add_options()" avail?
by U.Mutlu 15 Feb '15

15 Feb '15

Hi, I'm newbie to 'program options'. I just wanted to ask if there is an alternative for the below example from the online-doc: desc.add_options() ("help", "produce help message") ("compression", po::value<int>(), "set compression level") ; I would like to have something more traditional like the following single element addition alternative: desc.add_option("help", "produce help message"); desc.add_option("compression", po::value<int>(), "set compression level"); Is something like this already in the library? -- TIA Uenal

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meta state machine, process_event need to copy given event
by SBAM 13 Feb '15

13 Feb '15

Hello Christophe, I'm a boost msm first time user and I'm attempting to pass an event to my msm that cannot be copied. This event contains a /unique_ptr/ and my goal is to eventually steal it and store it under my msm. However, even with no deferred events, events are /copied/ to an internal queue, in /boost::msm::back::state_machine::do_pre_msg_queue_helper/. I just wanted to know if there was any chance /process_event/ could be overloaded and accept rvalue-ref or if by design, it's absolutely mandatory to copy those events. Many thanks for your great library -- View this message in context: http://boost.2283326.n4.nabble.com/meta-state-machine-process-event-need-to… Sent from the Boost - Users mailing list archive at Nabble.com.

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Performance optimization in Boost using std::vector<>
by saloo 12 Feb '15

12 Feb '15

Hello everybody, I have a question related to performance optimization using Boost. I found this link http://www.boost.org/doc/libs/1_41_0/doc/html/mpi/performance.html <http://www.boost.org/doc/libs/1_41_0/doc/html/mpi/performance.html> and trying to figure out which curve (on the graph in the link) represents the communication of std::vector<int> and std::vector<double>? Is communication using std::vector<int> and std::vector<double> optimized (is_mpi_datatype) or not? So I use "boost_mpi" and "boost_serialization" libraries. I include the header "#include <boost/serialization/vector.hpp>" in my code. Then I send directly std::vector<int> and std::vector<double> using "world.send(...) " and world.recv(...)" calls. I fill the vector with some values (for example I fill ten values) and I get the same ten values on other side of processor boundary. This thing works but I want to improve communication performance. I found out in this link http://www.boost.org/doc/libs/1_57_0/doc/html/mpi/tutorial.html under section "User-defined data types" that "Fixed data types can be optimized for transmission using the is_mpi_datatype type trait. ". Also I studied the information on http://www.boost.org/doc/libs/1_57_0/doc/html/mpi/tutorial.html#mpi.perform…. Also this link http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/wrappers.html#a… shows that std::vector<> are optimized for serialization. I am now confused that sending std::vector<> like this is good for performance optimization or not? What other better methods are available? Is something like this http://www.boost.org/doc/libs/1_57_0/doc/html/mpi/tutorial.html#mpi.skeleto… a good option? Best Regards, Salman Arshad -- View this message in context: http://boost.2283326.n4.nabble.com/Performance-optimization-in-Boost-using-… Sent from the Boost - Users mailing list archive at Nabble.com.

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Min cut between two vertices, undirected graph
by Mads Jensen 12 Feb '15

12 Feb '15

Hi, The Stoer Wagner implementation only takes as input a complete graph, and then it computes the min cut with the parity map indicating which cut set the vertex belongs to. I need something for computing the minimum cut between two arbitrary vertices given as input for an undirected graph. Edmonds Karps works just for a directed graph. Any help with this will be highly appreciated. -- Med Venlig Hilsen / Kind regards, Mads Jensen Max Jerry Horovitz: "Unfortunately, in America, babies are not found in cola cans. I asked my mother when I was four and she said they came from eggs laid by rabbis. If you aren't Jewish, they're laid by Catholic nuns. If you're an atheist, they're laid by dirty, lonely prostitutes." -- Mary and Max (2009)

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Which URL should I use in ExternalProject_Add
by Yi-Hong Lyu 11 Feb '15

11 Feb '15

Hello all, I used CMake's ExternalProject_Add to download and build boost in my project. The URL I used is ' http://sourceforge.net/projects/boost/files/boost/1.55.0/boost_1_55_0.zip/d…' and it works. However I got an error several days ago like: CMake Error: Problem with archive_read_open_file(): Unrecognized archive format It seems that what I download by CMake becomes 'HTML document, ASCII text' rather than 'Zip archive data, at least v2.0 to extract'. Could you tell me which URL should I use in ExternalProject_Add? Thanks, Yi-Hong

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boost iOS8 failure
by David Medine 11 Feb '15

11 Feb '15

First of all, I know that calls for help are not appropriate to the list, so let me disclaim by saying that I am not asking for help, simply reporting an issue. I am attempting to compile a C++ library (that uses boost) for iOS8 distribution. The library compiles fine on OSX (and Linux and Windows) but will not compile for iOS8. I get dozens of compiler complaints regarding boost headers that all involve some sort of 'Semantic Issue'. For example, in boost's hash.hpp, I get a 'No matching function for call to 'has_value' error on these lines (439-442): | BOOST_HASH_SPECIALIZE_REF(std::string) #if !defined(BOOST_NO_STD_WSTRING) BOOST_HASH_SPECIALIZE_REF(std::wstring) #endif | In this case I was able to skirt the issue by adding code to define the function hash_value for std::string and std::wstring: inline std::size_t hash_value( std::string const &v) { return hash_range(v.begin(), v.end()); } inline std::size_t hash_value( std::wstring const &v) { return hash_range(v.begin(), v.end()); } I am probably going to go through all such failures of clang to interpret the boost code correctly for iOS compilation and modify the source just so I can get this going. This is a major pain because there are dozens of these, many of which are far less straightforward to remedy. Besides I don't necessarily want a custom version of boost that ships with my library. I have the build settings in my iOS project (I'm using XCode) exactly the same as they are in the OSX project. I don't understand why the compiler behaves differently for these two targets. Finally, there are two stackoverflow questions that I posted related to this problem. http://stackoverflow.com/questions/28422862/clang-different-when-compiling-… http://stackoverflow.com/questions/28308466/ios8-boost-hash-hpp-system-cloc… THX!

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[gsoc15] Google Summer of Code 2015 ideas needed before 20th Feb
by Niall Douglas 10 Feb '15

10 Feb '15

Dear Boost community, The Google Summer of Code 2015 organisation application period has begun. We need project ideas for our ideas page at https://svn.boost.org/trac/boost/wiki/SoC2015, plus anyone willing to mentor. Last year we got eight slots, the previous year seven slots. Let's try to get back to ten slots for 2015! Niall & Boris --- Boost C++ Libraries Google Summer of Code 2015 admin https://svn.boost.org/trac/boost/wiki/SoC2015

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Problems/crash update a Spirit grammar from Boost 1.47 to 1.57
by Christoph Duelli 10 Feb '15

10 Feb '15

Updating Boost from 1.47 to 1.57 the code no longer compiles. It boils down to Both these includes are included (at various places) and these 2 lines compiled in 1.47 but no longer under 1.57. #include <boost/spirit/home/qi.hpp> #include <boost/spirit/home/phoenix.hpp> Changing #include <boost/spirit/home/phoenix.hpp> to #include <boost/phoenix.hpp> the code does compile, but causes crashes while parsing. (I was not able yet to narrow that down.) Is the correct way of porting a 1.47 boost spirit grammar to 1.57, to replace the old phoenix V2 header to #include <boost/phoenix.hpp> ? (Are there known issues? Or is there a "porting howto"?) Or is it still possible to use Spirit with Phoenix V2? Best regards -- Christoph Duelli --------------------------------------------------------------------------------- MELOS-Medizinische Labor-Organisations-Systeme GmbH Franz-Beer-Straße 6 86459 Gessertshausen Tel.: +49 8238/9611-0 Fax: +49 8238/9611-99 mailto: info(a)melosgmbh.de URL: www.melosgmbh.de Amtsgericht Augsburg, HRB 13226 USt-IdNr. DE 130 958 139 Geschäftsführer: Herbert Mayer, Andreas Manntz, Helmut Welsch -------------------------------------------- This e-mail (including any attachments) is confidential and may be privileged. If you have received it by mistake, please notify the sender by e-mail and delete it from your system. Any unauthorised use or dissemination of this e-mail or its contents in whole or in part is strictly prohibited. Please note that e-mails are susceptible to change. MELOS GmbH shall not be liable for the improper or incomplete transmission of the information contained in this communication nor for any delay in its receipt. MELOS GmbH does not guarantee that the integrity of this communication has been maintained nor that this communication is free of viruses, interceptions or interference.

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[gsoc15] Attn: We need 2015 mentors and project ideas for Boost!
by Niall Douglas 10 Feb '15

10 Feb '15

Dear Boost community, We are now within one month of the beginning of Google Summer of Code 2015! Last year's GSoC furthered the continuing success of the Boost GSoC programme with the first ever Boost funded extension to a GSoC project (that being Boost.Hana by Louis Dionne mentored by Joel Falcou, congrats to both of them on passing an exceptionally tough selection process), and over $50,000 of Google funding brought to Boost in 2014. We also sent three representatives to last year's mentor summit, including one student whose entire expenses the Boost Steering Committee very generously covered. As part of filling in our application for 2015, we must supply to Google a list of potential GSoC mentors and potential GSoC projects for summer 2015. There are a number of changes to how we design project ideas for students this year intended to improve the GSoC experience for both students and mentors, so please examine the ideas page which outlines those changes at https://svn.boost.org/trac/boost/wiki/SoC2015 and if you have any questions or concerns about those changes, please ask now rather than just before the GSoC deadline. 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 acquired eight slots from Google and had to disappoint two mentors and students, we hope with the improved selection process we can get back to the ten annual slots we once had. 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. Thank you in advance for your time. Niall Douglas (Boost Google Summer of Code admin) Boris Schäling (Boost Google Summer of Code admin) --- Boost C++ Libraries Google Summer of Code 2014 admin https://svn.boost.org/trac/boost/wiki/SoC2014

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[iostreams] How to utilize zlib setDictionary method
by Ringel, Rick 10 Feb '15

10 Feb '15

I have a use-case that requires highly efficient bandwidth utilization over a narrow WAN connection, where communication is message-oriented. I have successfully used boost to gzip, zlib, and bzip2 my messages, and ran some numbers (bzip2 is best so far). However, in researching and profiling zlib's native API, I found I could improve efficiently by an additional 15% over bzip2 by using zlib's SetDictionary methods for deflate and inflate. How would I go about extending boost:iostream's zlib_compressor and zlib_decompressor classes to utilized a predefined/static dictionary? Or, is it best just to use zlib's API directly, and bypass boost for this specialized zlib compression case? -Rick

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Re: [Boost-users] Boost-users Digest, Vol 4049, Issue 1
by David Frank 09 Feb '15

09 Feb '15

Thanks Howard ! On Monday, February 9, 2015 12:00 PM, "boost-users-request(a)lists.boost.org" <boost-users-request(a)lists.boost.org> wrote: Send Boost-users mailing list submissions to boost-users(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.boost.org/mailman/listinfo.cgi/boost-users or, via email, send a message with subject or body 'help' to boost-users-request(a)lists.boost.org You can reach the person managing the list at boost-users-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." Today's Topics: 1. Re: Signals2 benchmark (Klaim - Jo?l Lamotte) 2. Re: Signals2 benchmark (Michael Powell) 3. write starvation of upgradable lock (David Frank) 4. Re: write starvation of upgradable lock (Howard Hinnant) 5. Re: Signals2 benchmark (Nevin Liber) 6. Re: [Serialization] XML: float format is scientific instead of human-readable since Boost 1.57 (Frank St?hr) 7. Re: Signals2 benchmark (Dominique Devienne) ---------------------------------------------------------------------- Message: 1 Date: Sun, 8 Feb 2015 18:49:06 +0100 From: Klaim - Jo?l Lamotte <mjklaim(a)gmail.com> To: Boost users list <boost-users(a)lists.boost.org> Subject: Re: [Boost-users] Signals2 benchmark Message-ID: <CAOU91ON-+ywWjniue3n56sYSy2ZALtYykDN9ehLp4Qcm6BYoxg(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" On Sun, Feb 8, 2015 at 4:42 PM, Michael Powell <mwpowellhtx(a)gmail.com> wrote: > On Sun, Feb 8, 2015 at 8:02 AM, Klaim - Jo?l Lamotte <mjklaim(a)gmail.com> > wrote: > > > > > > An executor takes arbitrary tasks as input and only > > guarantee that these tasks will be executed, under some constraints > > defined by the specific executor type. > > A signal dispatch it's call and parametters to a set of observers. > > Using the Boost.Signals2 for example, it is easy AFAIK to type-define > a signal, and re-use that type anywhere that signal is required. So a > listener could receive a signal, and subsequently do whatever it > wanted to with that message; dispatch it again, process it, > whatever... > > Yes but the executor would specify how the observers are notified, not how the observer's work is executed (which depends on the observer implementation indeed). There is an important nuance here.

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boost variant + boost serialization unused type
by Merrill Cornish 09 Feb '15

09 Feb '15

Using boost::variant with boost::serialization gives me a warning about unused type in the boost::serialization namespace: D:/Boost/boost/serialization/variant.hpp:69:75: warning: typedef 'types' locally defined but not used [-Wunused-local-typedefs] typedef typename boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)>::types types; I looked up boost::ignore_unused, which says it's for unused types also, but everything I've tried for using in my code (following the definition of my variant) results in a syntax error or other bug claim. How should I use ignore_unused in this case?

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[Serialization] XML: float format is scientific instead of human-readable since Boost 1.57
by Frank Stähr 09 Feb '15

09 Feb '15

Hello Boost guys, when I switched from Boost 1.55 to 1.57 there was a change in the formation of floats and doubles for xml archives. Look at this example: #include <fstream> #include <boost/archive/xml_oarchive.hpp> class MyClass { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & boost::serialization::make_nvp("accuracy", accuracy); } double accuracy = 0.03; }; int main() { MyClass obj; std::ofstream ofs("sample.xml"); boost::archive::xml_oarchive oa(ofs); oa & boost::serialization::make_nvp("myclass", obj); } I compiled it with VS 2013 for 32 bit. The output file has the line: <m_accuracy>2.99999999999999990e-002</m_accuracy> In Boost 1.55 it was much better human-readable: 0.03. Is this behaviour (this change) intended? In any case, what is the best way to format floats and doubles? (i. e. a manipulator for the ofstream?) Thanks, Frank -- Frank Stähr Technische Universität Berlin Communication Systems Group Sekr. EN1 Einsteinufer 17 10587 Berlin, Germany

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write starvation of upgradable lock
by David Frank 09 Feb '15

09 Feb '15

From this discussion, http://stackoverflow.com/questions/21773618/starvation-with-upgrade-lock?no… There seems to be a starvation of writer with upgradable lock, I'm wondering if there is any fix/improvement with later release, e.g, 1.56, or 1.57 Thanks,David

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[website] File appears truncated
by Joaquin M Lopez Munoz 07 Feb '15

07 Feb '15

The following file (which is linked from Boost.MultiIndex docs): http://www.boost.org/doc/libs/1_57_0/libs/multi_index/example/hashed.cpp appears truncated at line 8, yet it is perfectly OK in github: https://github.com/boostorg/multi_index/blob/master/example/hashed.cpp Any clue what's going on? Thank you, Joaquín M López Muñoz Telefónica

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[System] Link issues using BOOST_ERROR_CODE_HEADER_ONLY
by Jonathan Jones 07 Feb '15

07 Feb '15

Hello, We're in the process of upgrading from Boost 1.49 to Boost 1.56. As part of this upgrade, we've noticed the linkage requirements for using the "system" library are much more strict in 1.56. We are getting linker errors like the following across dozens of our libraries: boost/system/error_code.hpp: undefined reference to `boost::system::generic_category()' boost/system/error_code.hpp: undefined reference to `boost::system::system_category()' We decided to fix these by defining the macro BOOST_ERROR_CODE_HEADER_ONLY according to this link: http://www.boost.org/doc/libs/1_56_0/libs/system/doc/reference.html#Header- error_code However, when building Boost itself with this macro defined, we're encountering several problems: 1) Some Boost libraries (chrono, filesystem, random) that use the "system" library no longer link, as if they are still expecting the library to be present. Note that some libraries, like thread, that use "system", link fine without the shared library being present. 2) We get multiple definitions of "boost::system::throws" Any thoughts on how to resolve these? Google search has not turned up any bugs that I can find. Sincerely, Jonathan Jones

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