July 2013 - Boost-users - lists.preview.boost.org

[Boost.Math special functions] Critical error in zeta.hpp, Boost 1.54.0
by Rainer Deyke 04 Jul '13

04 Jul '13

I'm getting compile errors when including "boost/math/special_functions/zeta.hpp" (which in turn is included indirectly by "boost/random.hpp"). This is in the recently released "boost_1_54_0.tar.bz2" under Linux Mint 16 for amd64, gcc 4.7.3. Minimal test case: #include "boost/math/special_functions/zeta.hpp" int main() {} Exact error message: In file included from source/eldwood/test/zeta.cpp:1:0: intermediate/usr_x86_64-pc-linux-gnu/include/boost/math/special_functions/zeta.hpp: In function ‘T boost::math::detail::zeta_imp(T, T, const Policy&, const Tag&)’: intermediate/usr_x86_64-pc-linux-gnu/include/boost/math/special_functions/zeta.hpp:877:24: error: ‘log_root_two_pi’ is not a member of ‘boost::math::constants’ intermediate/usr_x86_64-pc-linux-gnu/include/boost/math/special_functions/zeta.hpp:877:52: error: expected primary-expression before ‘,’ token intermediate/usr_x86_64-pc-linux-gnu/include/boost/math/special_functions/zeta.hpp:877:60: error: expected primary-expression before ‘>’ token intermediate/usr_x86_64-pc-linux-gnu/include/boost/math/special_functions/zeta.hpp:877:62: error: expected primary-expression before ‘)’ token The same error also manifests under clang. -- Rainer Deyke (rainerd(a)eldwood.com)

3 2

Boost 1.54.0: bootstrap build fails for MinGW/MSYS
by Josue Andrade Gomes 04 Jul '13

04 Jul '13

Hi, Bjam build is failing for me on MinGW/MSYS. ================================================================================ Boost 1.54.0: $ cd boost_1_54_0/tools/build/v2/engine $ ./build.sh mingw ### ### Using 'mingw' toolset. ### rm -rf bootstrap mkdir bootstrap gcc -DNT -o bootstrap/jam0 command.c compile.c constants.c debug.c execcmd.c frames.c function.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c object.c option.c output.c parse.c pathsys.c pathunix.c regexp.c rules.c scan.c search.c subst.c timestamp.c variable.c modules.c strings.c filesys.c builtins.c class.c cwd.c native.c md5.c w32_getreg.c modules/set.c modules/path.c modules/regex.c modules/property-set.c modules/sequence.c modules/order.c execnt.c filent.c ./bootstrap/jam0 -f build.jam --toolset=mingw --toolset-root= clean ...found 1 target... ...updating 1 target... ...updated 1 target... ./bootstrap/jam0 -f build.jam --toolset=mingw --toolset-root= don't know how to make modules/set.c don't know how to make modules/path.c don't know how to make modules/regex.c don't know how to make modules/property-set.c don't know how to make modules/sequence.c don't know how to make modules/order.c ...found 126 targets... ...updating 1 target... ...can't find 6 targets... ...can't make 2 targets... failed to write command file! ================================================================================ Boost 1.53.0: $ cd boost_1_53_0/tools/build/v2/engine $ ./build.sh mingw ### ### Using 'mingw' toolset. ### rm -rf bootstrap mkdir bootstrap gcc -DNT -o bootstrap/jam0 command.c compile.c constants.c debug.c function.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c lists.c make.c make1.c object.c option.c output.c parse.c pathunix.c regexp.c rules.c scan.c search.c subst.c timestamp.c variable.c modules.c strings.c filesys.c builtins.c pwd.c class.c native.c md5.c w32_getreg.c modules/set.c modules/path.c modules/regex.c modules/property-set.c modules/sequence.c modules/order.c execnt.c filent.c ./bootstrap/jam0 -f build.jam --toolset=mingw --toolset-root= clean ...found 1 target... ...updating 1 target... ...updated 1 target... ./bootstrap/jam0 -f build.jam --toolset=mingw --toolset-root= ...found 50 targets... ...updating 3 targets... [MKDIR] bin.ntx86 [COMPILE] bin.ntx86\b2.exe [COPY] bin.ntx86\bjam.exe ...updated 3 targets... Any idea? Thanks & regards josue -- Josue Andrade Gomes josuegomes.com

2 2

async processing issues
by SRD 04 Jul '13

04 Jul '13

Having a tough time learning ASIO. I'm trying to have one thread constantly listen for new file monitoring events (mthread) while another thread processes one task at a time (wthread). Somehow I'm still losing events that don't get placed on the task_queue and it would seem that once an event is lost, the file_handler callback for the dir_monitor stops working thereafter for good. So I'm having a few issues with my solution. If I comment out the sleep() method below, then for some reason the first two lines that have to do with the dir_monitor immediately after the while loop quickly eat through all available memory and the program will soon crash within a minute or two. Leaving the sleep in keeps things stable, or maybe it just eats away so slowly I don't notice it. Leaving sleep() in also has the problem of *I think* causing missed file events. The f_handler() function posts tasks that I create within the dir_monitor callback back to the main thread via the io_service.post(), but if its asleep, will it be able to place objects on the main processes task_queue? I think thats one point where I'm going wrong. If anyone sees where I'm going wrong, any help much appreciated. --- static queue<TaskObj *> task_queue; boost::asio::io_service io_service; void queue_task(TaskObj *task) { // pass task back to main thread. task_queue.push(task); } void f_handler(const boost::system::error_code &ec, const boost::asio::dir_monitor_event &ev) { TaskObj task = new TaskObj(...); // create task and place on queue by posting to main process io_service.post(boost::bind(queue_task, task)); } int main(...) { boost::asio::io_service work_service; boost::asio::dir_monitor dm(io_service); dm.async_monitor(f_handler); // dir_monitor thread boost::thread mthread = boost::thread(boost::bind(&boost::asio::io_service::run, boost::ref(io_service))); // setup work to prevent premature exit shared_ptr<boost::asio::io_service::work> work(new boost::asio::io_service::work(work_service)); // worker thread boost::thread wthread(boost::bind(&boost::asio::io_service::run, boost::ref(work_service))); wthread.detach(); while (true) { io_service.reset(); dm.async_monitor(f_handler); // losing all available memory from above two lines without the sleep() below // get first task off of queue and process in worker thread task = task_queue.front(); // functor executed in seperate thread work_service.post(boost::bind(&TaskObj::do_it, task)); sleep(3); }

2 4

Confused with Depth-First-Search method, forward or cross edge found on a undirected graph ?
by lizy10b 03 Jul '13

03 Jul '13

Hi there I have a problem with the DFS method (Boost 1.53). I found when invoking the DFS method on a undirected graph, the "forward_or_cross_edge" was called more than one times. But as the document says "In an undirected graph this method is never called". http://www.boost.org/doc/libs/1_53_0/libs/graph/doc/DFSVisitor.html I performed the test based on the file_dependencies.cpp example (examples/file_dependencies.cpp; http://www.boost.org/doc/libs/1_53_0/libs/graph/doc/file_dependency_example…) 1) Change the graph type from "bidirectionalS" to "undirected". 2)Implement all the 8 DFS vistor "event methods" (Initialize Vertex, Start Vertex, Discover Vertex, Examine Edge, Tree Edge, Back Edge, Forward or Cross Edge, Finish Vertex) in the cycle_detector struct to print the vertex names, edge sources and targets. 3)comment out some code at the begining of the example cpp files as the topological_sort method raise exception upon the undirected graph. The results: the forward_or_cross_edge method was called five times. initialize_vertex: dax.h initialize_vertex: yow.h initialize_vertex: boz.h initialize_vertex: zow.h initialize_vertex: foo.cpp initialize_vertex: foo.o initialize_vertex: bar.cpp initialize_vertex: bar.o initialize_vertex: libfoobar.a initialize_vertex: zig.cpp initialize_vertex: zig.o initialize_vertex: zag.cpp initialize_vertex: zag.o initialize_vertex: libzigzag.a initialize_vertex: killerapp start_vertex: dax.h discover_vertex: dax.h examine_edge: dax.h --> foo.cpp tree_edge: dax.h --> foo.cpp discover_vertex: foo.cpp examine_edge: foo.cpp --> dax.h back_edge: foo.cpp --> dax.h examine_edge: foo.cpp --> zow.h tree_edge: foo.cpp --> zow.h discover_vertex: zow.h examine_edge: zow.h --> foo.cpp back_edge: zow.h --> foo.cpp finish_vertex: zow.h examine_edge: foo.cpp --> foo.o tree_edge: foo.cpp --> foo.o discover_vertex: foo.o examine_edge: foo.o --> foo.cpp back_edge: foo.o --> foo.cpp examine_edge: foo.o --> libfoobar.a tree_edge: foo.o --> libfoobar.a discover_vertex: libfoobar.a examine_edge: libfoobar.a --> foo.o back_edge: libfoobar.a --> foo.o examine_edge: libfoobar.a --> bar.o tree_edge: libfoobar.a --> bar.o discover_vertex: bar.o examine_edge: bar.o --> bar.cpp tree_edge: bar.o --> bar.cpp discover_vertex: bar.cpp examine_edge: bar.cpp --> dax.h back_edge: bar.cpp --> dax.h examine_edge: bar.cpp --> yow.h tree_edge: bar.cpp --> yow.h discover_vertex: yow.h examine_edge: yow.h --> dax.h back_edge: yow.h --> dax.h examine_edge: yow.h --> bar.cpp back_edge: yow.h --> bar.cpp examine_edge: yow.h --> zag.cpp tree_edge: yow.h --> zag.cpp discover_vertex: zag.cpp examine_edge: zag.cpp --> yow.h back_edge: zag.cpp --> yow.h examine_edge: zag.cpp --> boz.h tree_edge: zag.cpp --> boz.h discover_vertex: boz.h examine_edge: boz.h --> bar.cpp back_edge: boz.h --> bar.cpp examine_edge: boz.h --> zig.cpp tree_edge: boz.h --> zig.cpp discover_vertex: zig.cpp examine_edge: zig.cpp --> boz.h back_edge: zig.cpp --> boz.h examine_edge: zig.cpp --> zig.o tree_edge: zig.cpp --> zig.o discover_vertex: zig.o examine_edge: zig.o --> zig.cpp back_edge: zig.o --> zig.cpp examine_edge: zig.o --> libzigzag.a tree_edge: zig.o --> libzigzag.a discover_vertex: libzigzag.a examine_edge: libzigzag.a --> libfoobar.a back_edge: libzigzag.a --> libfoobar.a examine_edge: libzigzag.a --> zig.o back_edge: libzigzag.a --> zig.o examine_edge: libzigzag.a --> zag.o tree_edge: libzigzag.a --> zag.o discover_vertex: zag.o examine_edge: zag.o --> zag.cpp back_edge: zag.o --> zag.cpp examine_edge: zag.o --> libzigzag.a back_edge: zag.o --> libzigzag.a finish_vertex: zag.o examine_edge: libzigzag.a --> killerapp tree_edge: libzigzag.a --> killerapp discover_vertex: killerapp examine_edge: killerapp --> libzigzag.a back_edge: killerapp --> libzigzag.a finish_vertex: killerapp finish_vertex: libzigzag.a finish_vertex: zig.o finish_vertex: zig.cpp examine_edge: boz.h --> zag.cpp back_edge: boz.h --> zag.cpp finish_vertex: boz.h examine_edge: zag.cpp --> zag.o forward_or_cross_edge: zag.cpp --> zag.o !!!!!! finish_vertex: zag.cpp finish_vertex: yow.h examine_edge: bar.cpp --> boz.h forward_or_cross_edge: bar.cpp --> boz.h !!!!!! examine_edge: bar.cpp --> bar.o back_edge: bar.cpp --> bar.o finish_vertex: bar.cpp examine_edge: bar.o --> libfoobar.a back_edge: bar.o --> libfoobar.a finish_vertex: bar.o examine_edge: libfoobar.a --> libzigzag.a forward_or_cross_edge: libfoobar.a --> libzigzag.a !!!!!! finish_vertex: libfoobar.a finish_vertex: foo.o finish_vertex: foo.cpp examine_edge: dax.h --> bar.cpp forward_or_cross_edge: dax.h --> bar.cpp !!!!!! examine_edge: dax.h --> yow.h forward_or_cross_edge: dax.h --> yow.h !!!!!! finish_vertex: dax.h What is the problem? Thanks. Zhiyu 2013-06-24 lizy10b

3 23

Applied GUI on chat server/client examples of boost.asio
by Journeyer J. Joh 03 Jul '13

03 Jul '13

Hi list, This is not a question nor an answer. And not an advertisement. I made an ultra simple GUI on boost.asio example code below. http://www.boost.org/doc/libs/1_53_0/doc/html/boost_asio/examples.html My code is on github. https://github.com/Journeyer/wxboost It is implemented from wxwidgets example code for wxTextCtrl under samples/text I don't have any purpose on this post. If anyone cloned my source code and compile and runs he/she would be able to talk with me and with anyone who did the same experiment. My chat server is running until it breaks. I am doing this just for fun ^^; FYI: build environment is Ubuntu/GCC/gtk/wxwidgets/boost Windows7/MinGW/wxwidgets/boost Best regards Journeyer ---------------------------------------- Journeyer J. Joh o o s a p r o g r a m m e r a t g m a i l d o t c o m ----------------------------------------

2 2

[build] Build with multiple processes under MSVC10
by Igor R 03 Jul '13

03 Jul '13

Hello, Is the subj possible? Adding "cxxflags=/MP" to b2 line doesn't seem to work. Thanks.

2 2

single thread in loop
by SRD 03 Jul '13

03 Jul '13

I'm using boost 1.53 on windows 7. I have a main loop which runs some checks and when events are received, results in callbacks that add tasks onto a queue. I then pull a task off the queue, wish to start a thread (and only one thread) to handle the task, and continue to loop checking for certain events. And each time I go through the loop, I want to check to see if the current thread has completed before pulling off another task to process. My problem is that I'm not sure how to write the thread in to do this and not join because I have to keep looping to check for certain events. void my_callback(...); MyTask *task; while (true) { event_checks(); switch(state) { case STATE1: if (!queue.empty()) task = queue.front(); // ... break; case STATE2: // check if thread is still running, otherwise, start new thread boost::thread(&MyTask::do_it, task); // ... break; // ... } I tried things similar to the below but couldn't get that quite right. boost::thread t; while (true) { // ... if (t.timed_join(0) == false) { t = boost::thread(&MyTask::do_it, task); } // ... Any help much appreciated.

2 3

Thread pools and Boost Asio
by Rodrigo Madera 02 Jul '13

02 Jul '13

Hey there. I use Boost Asio for async code everywhere in C++, even where there is absolutely no IO whatsoever. Just (ab)using Asio "for the async of it." Searching the net for the current status of async frameworks for C++, I see that there is an unofficial (please correct me if I'm wrong) threadpool library. Will it become official? If not, does the Boost community offer something simpler than Asio for this? I just feel that I'm abusing Asio, where something simpler would suffice. And threadpool might be it. Would be nice to see if other people are async'ing out there. Best regards, Rodrigo Madera

2 1

[asio] Getting started with strand
by Michael Powell 02 Jul '13

02 Jul '13

Hello, I want to get started using asio strand if at all possible. Getting started, however, I am struggling with a couple of errors/issues. For starters: * Cannot find std::enable_shared_from_this, std::move: they do not exist in our environment. * From there a ton of what look like steady-timer-related errors. Many of the errors are linker errors I think. Symbols cannot be resolved, such like this. I am pretty sure I am linking with the correct Boost libraries (statically, multi-threaded). Possibly need to rebuild Boost with different compiler settings? Also, possibly we do not have the correct compile-time switches enabled. Possibly also not linking with the correct libraries. We are cross-compiling into ArchLinux for ARM using Sourcery CodeBench, basically a GCC 4.7.2 based environment. That or are we stuck with the old-style approach to scheduling asio io_service callbacks? Would much prefer strands if we can somehow manage it. Thank you... Regards, Michael Powell

1 2

boost 1.54 and intel compiler ?
by avib369 . 02 Jul '13

02 Jul '13

I have noticed that the Intel Compiler is no longer mentioned ? Has this compiler been dropped ? Ta, Avi

3 2