April 2014 - Boost - lists.preview.boost.org

Re: [boost] [graph/adjacency_list] edge have many costs
by Jeremiah Willcock 10 Apr '14

10 Apr '14

On Tue, Apr 8, 2014 6:59 AM PDT aymen kaabi wrote: >Good morning, > > >I want to create a graph that their egdes have array of cost ( i dont mean >bundle property) because i want to create this graph and try dijikstra for >every cost values . >can i have an example. > >example: graph have 2 edge 1->2 ( cost 1,2,3,4,7) > 2->3(cost 2,5,3,8,9) > >thanks for your helps Edges can have arbitrary properties, so you can create a graph whose edge weight property is a container type. What are you planning to use the multiple weights for? For some uses, parallel edges between the same vertices might make sense to consider as well. -- Jeremiah Willcock

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Re: [boost] [BGL] Visual Studio 12 finish_edge() failure, general BOOST_TTI_HAS_MEMBER_FUNCTION failure?
by Jeremiah Willcock 10 Apr '14

10 Apr '14

On Tue, Apr 1, 2014 1:12 PM PDT Michael Behrns-Miller wrote: >On 4/1/2014 8:45 AM, Edward Diener wrote: >> On 4/1/2014 4:50 AM, Michael Behrns-Miller wrote: >> On 4/1/2014 4:40 AM, Michael Behrns-Miller wrote: >>> On 3/31/2014 6:30 PM, Edward Diener wrote: >>> On 3/31/2014 1:27 PM, Michael Behrns-Miller wrote: >>>> ... >>>> Here's how BGL defines it: >>>> >>>> ------------- >>>> >>>> BOOST_TTI_HAS_MEMBER_FUNCTION(finish_edge) >>>> >>>> template <bool IsCallable> struct do_call_finish_edge { >>>> template <typename E, typename G, typename Vis> >>>> static void call_finish_edge(Vis& vis, const E& e, const G& g) { >>>> vis.finish_edge(e, g); >>>> } >>>> }; >>>> >>>> template <> struct do_call_finish_edge<false> { >>>> template <typename E, typename G, typename Vis> >>>> static void call_finish_edge(Vis&, const E&, const G&) {} >>>> }; >>>> >>>> template <typename E, typename G, typename Vis> >>>> void call_finish_edge(Vis& vis, const E& e, const G& g) { // Only >>>> call if method exists >>>> do_call_finish_edge<has_member_function_finish_edge<Vis, >>>> void>::value>::call_finish_edge(vis, e, g); >>>> } >>> >>> The invocation of has_member_function_finish_edge has to match the >>> member function signature which you are invoking. If the member >>> function signature for finish_edge is: >>> >>> void finish_edge(const E&, const G&); >>> >>> then your invocation for do_call_finish_edge must be: >>> >>> do_call_finish_edge >>> < >>> has_member_function_finish_edge >>> < >>> Vis, >>> void, >>> boost::mpl::vector >>> < >>> const E&, >>> const G& >>> > >>> > >>> ::value >>> >::call_finish_edge(vis, e, g); >>> >>> or >>> >>> do_call_finish_edge >>> < >>> has_member_function_finish_edge >>> < >>> void Vis::* (const E&,const G&) >>> > >>> ::value >>> >::call_finish_edge(vis, e, g); >>> >>> >>> _______________________________________________ >>> Unsubscribe & other changes: >>> http://lists.boost.org/mailman/listinfo.cgi/boost >>> >>> Thank you Edward. >>> >>> The instantiation code was not mine, that is what is done by the BGL, >>> here: >>> >>> boost\graph\depth_first_search.hpp >>> >>> The instantiation code does not seem to match your recommendation. >>> This simple DFS test fails: >>> >>> https://svn.boost.org/trac/boost/attachment/ticket/9770/test.cc >>> >>> So it sounds like BGL needs some patching to match your format. It >>> should change from... >>> >>> do_call_finish_edge<has_member_function_finish_edge<Vis, >>> void>::value>::call_finish_edge(vis, e, g); >>> >>> to... >>> >>> do_call_finish_edge<has_member_function_finish_edge<void Vis::* (const >>> E&,const G&)>::value>::call_finish_edge(vis, e, g); >>> >>> Does that sound correct? >> >> On the newer code, Visual Studio 12 gives me: >> >> boost_1_55_0/boost/graph/depth_first_search.hpp(86): error C2182: >> 'abstract declarator' : illegal use of type 'void' >> >> I am the developer for TTI. In your test case the actual VIZ struct has templated member functions, so I do not think has_member_function will find your templated functions. TTI is a compile-time mechanism for producing compile-time code. But even if it does not find the member functions at compile-time TTI should not produce a compile-time error so I definitely want to look at this situation. >> >> As to why Visual Studio 12 gives that error I need to be able to reproduce your compile steps. I am an absolute novice with the Boost graph library. I think I need to build the library first, then run your test against it. >> >> Jeremiah Willcock produced the changes in graph using TTI so he may have had a very good reason for using the original has_member_function signature, although it looks wrong to me on purely a TTI basis. Hopefully he will chime in on his change. >> >> >> >> _______________________________________________ >> Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost > >Thanks Edward, appreciate the feedback, I'll be monitoring. In the meantime my workaround of making finish_edge() non-optional is working for me. But of course I'd prefer not to have to change boost code before using. :-) > >Sure appreciate all you guys do to develop and maintain the libraries, boost is just fantastic. I wanted a way to test for equivalent signatures for the finish_edge member (copy vs. const ref, for example). I probably believed/saw somewhere that the syntax I used would do that. Is there a way to get a general "call ability" test for a member function using TTI? -- Jeremiah Willcock

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Error running ip_multicast (and ip_multicast_select) regression tests
by Chris Cooper 09 Apr '14

09 Apr '14

When I run the ip_multicast (and ip_multicast_select) regression tests for boost 1.55 on my Mac, they fail with these errors: ip/multicast.cpp:165: error in "ip_multicast_runtime::test": 49, Can't assign requested address ip/multicast.cpp:181: error in "ip_multicast_runtime::test": 49, Can't assign requested address I’m new to IPv6, but it looks like the regression test is making sure that IPv6 is available (multicast.cpp lines 128-132), and then it’s trying to join a IPv6 multicast group (lines 163-165) and leave it (lines 179-181), and failing both times. I’m not sure how to check whether multicast is enabled for IPv6 on this machine (which I’ve seen online as a possible reason for this failure), but then it seems like the regression test is not so great if it can fail due to the environment of the host computer instead of an actual bug in the boost library. Are there other reasons why this test would fail? Is there a way I can check whether multicast over IPv6 is allowed on this machine? Is there a recommended way to disable one particular subtest like this one? A #ifdef kind of thing? Thanks, Chris

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[context] Don't hard-code the assembler
by Steven Watanabe 09 Apr '14

09 Apr '14

AMDG This commit: https://github.com/boostorg/context/commit/7534fe5d1c01e7f543d86607770e9c46… makes it impossible for me to run b2 --with-context msvc-12.0 outside of the visual studio command prompt. Please just use the assembler that the toolset provides. In Christ, Steven Watanabe

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Boost Parallel Graph Library: remove_vertex gives unexpected results
by Alok Kumbhare 09 Apr '14

09 Apr '14

Hi All, i need some help with parallel boost graph library. Sorry if this is not the right list to post. Posting here since it looks like it might be a but. In particular, i am trying to modify the structure of the graph (distributed adjacency list) after it is loaded. The code snippet is at http://pastebin.com/erizQ0Sf. The problem is that clear_vertex(v,g) and remove_vertex(v,g) does not seem to operate on the same vertex in the graph. Here is a sample graph in metis format: http://pastebin.com/qxy2w6aw (I use the default vertex distribution for this example) The graph_viz output is available here for different scenarios: https://onedrive.live.com/redir?resid=C3CDB6EFBD31B4A8!20818&authkey=!AJqEF…<https://onedrive.live.com/redir?resid=C3CDB6EFBD31B4A8!20818&authkey=!AJqEF…> As you can see in the above figure: The first image is the original graph split into two partitions (mpirun -np 2 ./test) The second image is after clear_vertex is called for one of the vertices. Notice vertex "0". All the edges are removed as expected. The third image is after remove_vertex is called (which is called after clear_vertex, as mentioned in the documentation here: http://www.boost.org/doc/libs/1_55_0/libs/graph_parallel/doc/html/distribut…) Notice here that the vertex "2" is removed instead of vertex "0" even when using the same vertex descriptor for both calls. One thing i noted is that the remove_vertex seems to remove the "last" vertex in that partition irrespective of the input. e.g. if i use v = vertex(1,g) in the above code, i still see that the vertex "2" is removed and the edges rearranged for that. Is this a bug or am i doing something wrong. Your help will be greatly appreciated. Thanks, Alok Kumbhare

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[wrapper]
by Alexandra 09 Apr '14

09 Apr '14

HI, I have Ubuntu 13.10 with a Processor Intel Pentium CPU P6100 2.00GHz x 2. I download the boost library for linux, extract and install boostrap.sh. When I try to do ./b2 on terminal, the result is this: MPI auto-detection failed: unknown wrapper compiler mpic++ Please report this error to the Boost mailing list: http://www.boost.org You will need to manually configure MPI support. /home/alexandra/boost_1_55_0/tools/build/v2/tools/gcc.jam:148: in gcc.init from module gcc error: toolset gcc initialization: error: no command provided, default command 'g++' not found error: initialized from project-config.jam:12 /home/alexandra/boost_1_55_0/tools/build/v2/build/toolset.jam:41: in toolset.using from module toolset /home/alexandra/boost_1_55_0/tools/build/v2/build/project.jam:1007: in using from module project-rules project-config.jam:12: in modules.load from module project-config /home/alexandra/boost_1_55_0/tools/build/v2/build-system.jam:249: in load-config from module build-system /home/alexandra/boost_1_55_0/tools/build/v2/build-system.jam:412: in load-configuration-files from module build-system /home/alexandra/boost_1_55_0/tools/build/v2/build-system.jam:524: in load from module build-system /home/alexandra/boost_1_55_0/tools/build/v2/kernel/modules.jam:289: in import from module modules /home/alexandra/boost_1_55_0/tools/build/v2/kernel/bootstrap.jam:139: in boost-build from module /home/alexandra/boost_1_55_0/boost-build.jam:17: in module scope from module On user-config.jam i wrote # ------------------ # MPI configuration. # ------------------ using mpi ; in the final line. You can help me? THank you Alexandra

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[filesystem] path noncopyable error with boost 1.55.0 and g++ 4.5.1
by Richard Hadsell 09 Apr '14

09 Apr '14

I am trying to upgrade from Boost 1.52 to 1.55. Everything is fine with Clang 3.3, but I get this error with G++ 4.5.1: In file included from /netDISKS/master/netmt/LINUX_INTF14/cgi/boost/1.55.0/Include/libboost/boost/system/error_code.hpp:18:0, from /netDISKS/master/netmt/LINUX_INTF14/cgi/boost/1.55.0/Include/libboost/boost/filesystem/path_traits.hpp:23, from /netDISKS/master/netmt/LINUX_INTF14/cgi/boost/1.55.0/Include/libboost/boost/filesystem/path.hpp:25, from bssConfig.h:24, from bssConfig.cc:13: /netDISKS/master/netmt/LINUX_INTF14/cgi/boost/1.55.0/Include/libboost/boost/noncopyable.hpp:27:37: error: 'boost::noncopyable_::noncopyable::noncopyable()' declared with non-public access cannot be defaulted in the class body /netDISKS/master/netmt/LINUX_INTF14/cgi/boost/1.55.0/Include/libboost/boost/noncopyable.hpp:28:22: error: 'boost::noncopyable_::noncopyable::~noncopyable()' declared with non-public access cannot be defaulted in the class body The OS is Linux Fedora 14. The compiler is gcc version 4.5.1 20100924 (Red Hat 4.5.1-4). I am compiling with these flags: -march=core2 -msse4.1 -m64 -mpc64 -std=c++0x -pedantic-errors -mieee-fp -fPIC -pthread -O2 -g -fno-strict-aliasing -fno-tree-ccp -- Dick Hadsell 203-992-6320 Fax: 203-992-6001 Reply-to: hadsell(a)blueskystudios.com Blue Sky Studioshttp://www.blueskystudios.com 1 American Lane, Greenwich, CT 06831-2560 Follow Blue Sky Studios on Facebook <http://www.facebook.com/BlueSkyStudios> and Twitter <http://twitter.com/#%21/blueskystudios>

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Reboot all the CREST server machines to apply the updated openssl lib
by Kim, DongInn 09 Apr '14

09 Apr '14

Dear All, I am advised to reboot all our CREST servers to fully apply the updated OpeeSSL library. The new OpenSSL library was patched to RHEL 6 (RedHat Enterprise Linux 6) packages yesterday and they were installed on all the CREST server machines at around 10am Apr 8, 2014. (Note: all the CREST server machines are setup with RHEL6). The OpenSSL bug is serious and we needed to take immediate actions. http://heartbleed.com Even though our server seem to be safe with the new OpenSSL library now, I would like to make sure that there is no any leaking spots in our server machines by refreshing all the systems with the new OpenSSL library. I would like to setup a schedule to reboot all the CREST server machines at 9am tomorrow (Apr 10, 2014). Date: April 10, 2014 Time: 6:00am-7:00am Pacific US time 7:00am-8:00am Mountain US time 8:00am-9:00am Central US time 9:00am-10:00am Eastern US time 1:00pm-2:00pm GMT Please let me know if you have any questions or concerns about rebooting our servers. Regards, -- - DongInn

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Compile error on function.mem_fun_cxx98 regression test
by Chris Cooper 09 Apr '14

09 Apr '14

I’m trying to get all of the regression tests to work on my Mac which is running OSX 10.9.2 with Xcode 5.1. "clang++ —version” reports “Apple LLVM version 5.1 (clang-503.0.38) (based on LLVM 3.4svn)”. I’m building the boost libraries for c++11. I realize boost 1.55 doesn’t officially support this compiler (yet) so I’m out on the bleeding edge, but it’s almost working. I am cheating a little by manually applying a few of the post-1.55 patches, and if I need to do that to get the regression tests to build that’s fine. When I try to compile function.mem_fun_cxx98 it gives me this error: mem_fun_cxx98.cpp:34:46: error: invalid operands to binary expression ('std::__1::basic_ostream<char>' and 'ostream' (aka 'basic_ostream<char>')) BOOST_TEST(f2(&x, boost::ref(std::cout)) == std::cout); ../../../boost/detail/lightweight_test.hpp:186:28: note: expanded from macro 'BOOST_TEST' #define BOOST_TEST(expr) ((expr)? (void)0: ::boost::detail::test_failed_impl(#expr, __FILE__, __LINE__, BOOST_CURRENT_FUNCTION)) 1 error generated. The error looked to me like a stdlib vs. libc++ kind of thing, so I double-checked the compiler options. For the regression test, bjam is calling the compiler like so: "clang++" -x c++ -std=c++11 -stdlib=libc++ -O3 -O3 -finline-functions -Wno-inline -Wall -DBOOST_ALL_NO_LIB=1 -DNDEBUG -I"../../.." -c -o "/tmp/boost/bin.v2/libs/function/test/mem_fun_cxx98.test/clang-darwin-4.2.1/release/link-static/threading-multi/libs/function/test/mem_fun_cxx98.o” “[SNIP]/mem_fun_cxx98.cpp" The boost libraries are build by calling the compiler: "clang++" -x c++ -std=c++11 -stdlib=libc++ -O3 -O3 -finline-functions -Wno-inline -Wall -DBOOST_ALL_NO_LIB=1 -DBOOST_COROUTINES_SOURCE -DBOOST_SYSTEM_STATIC_LINK=1 -DNDEBUG -I"." -c -o “[SNIP]/bin/boost/bin.v2/libs/coroutine/build/clang-darwin-4.2.1/release/link-static/threading-multi/exceptions.o" "libs/coroutine/src/exceptions.cpp" Whether I bootstrap for toolset clang or darwin doesn’t seem to change anything. Building the library and regression test using clang++ without the c++11 flags works correctly. Is this a known problem that has already been patched for the 1.56 release (I can’t find it if so)? Any suggestions on why this might be happening? Thanks, Chris

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[graph/adjacency_list] edge have many costs
by aymen kaabi 08 Apr '14

08 Apr '14

Good morning, I want to create a graph that their egdes have array of cost ( i dont mean bundle property) because i want to create this graph and try dijikstra for every cost values . can i have an example. example: graph have 2 edge 1->2 ( cost 1,2,3,4,7) 2->3(cost 2,5,3,8,9) thanks for your helps

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[serialization] proposed improvements: forward-compatibility of serialization
by Andrzej Horoszczak 08 Apr '14

08 Apr '14

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phoenix bind vs boost bind?
by Robert Dailey 07 Apr '14

07 Apr '14

First of all, I'm using boost 1.55.0 on MSVC9. I've been using boost::phoenix in various places in my code base for easier usage of std::for_each and friends. However, I do not create lazy functions for a lot of the functions I bind to because they are only needed in one place most of the time. As a result, I use boost::phoenix::bind the same as I'd use boost::bind(). However I have read in various places that boost::bind is being deprecated. I'm not sure if there is truth to this, but is there a reason to choose one over the other? Is phx::bind() basically an "upgrade" to boost::bind? If I intermingle them, I have a lot of issues out of placeholder ambiguities that results in more boilerplate code (i.e. using boost::phoenix::placeholders::_1 everywhere). Any tips? I haven't used boost in a few years so I just want to make sure I'm not using it incorrectly. Thanks in advance.

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Re: [boost] [container] Vector-like container, which takes, feedback for Jeremy M.
by Alexander Kuprijanov 07 Apr '14

07 Apr '14

> Message: 3 > Date: Sun, 6 Apr 2014 09:59:20 +1000 > From: Jeremy Murphy <jeremy.william.murphy(a)gmail.com> > On 6 April 2014 00:45, Alexander Kuprijanov <alexkupri(a)gmail.com> wrote: > >> Hi, everybody! >> The most important feature of my container is performance. However, other >> features will appear later. >> https://github.com/alexkupri/array/blob/master/description/description.txt >> Today I compared my container with rope. My container outperformed it 10 >> times. > > > Hi Alex, > > could you include a build file (I recommend CMake)? My cursory attempt to > compile main.cpp spewed lots of errors. Thanks, cheers. > > Jeremy > Hi, Jeremy! Well, I provided makefiles, but I'm not sure if they help. The line: g++ -O3 main.cpp worked well. If you still have problems, be specific and tell, which project (trunk or performance), which errors and which system. "trunk" should be compiled, because I checked it on Linux and Windows; performance is more platform specific and uses __gnu_cxx::rope. Best regards, A.K.

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Network change of the Boost main web/mail server (wowbagger)
by Kim, DongInn 07 Apr '14

07 Apr '14

Dear All, The boost server machine (wowbagger.crest.iu.edu) is requested to change its subnet and I am planning to switch its IP address for the change of the subnet. I have arranged the schedule to update the DNS information of the following hostnames in wowbagger. - www.boost.org - svn.boost.org - lists.boost.org - boostcon.boost.org - beta.boost.org - www.boostcon.org - wiki.boost.org The IP transition date and time: April 07, 2014 6:00am-7:00am Pacific US time 7:00am-8:00am Mountain US time 8:00am-9:00am Central US time 9:00am-10:00am Eastern US time 1:00pm-2:00pm GMT The list of services that may not be available: - Web services: www.boost.org svn.boost.org lists.boost.org ... - Mail services including mailing lists: boost(a)lists.boost.org boost-users(a)lists.boost.org … - Subversion svn.boost.org The old IP address: 129.79.13.33 The new IP address: 129.79.39.203 I have already prepared the IP transition on wowbagger to make the new IP address provide the same services on it so that I hope that there is no actual outage of the services other than the rebooting time. If you happened to use the IP address on your cronjob or programs, please make sure that you switch it with the new one. IMPORTANT ========================================= wowbagger will need to reboot to kick in a new kernel and mount the NFS space with the new IP address at the same time. ========================================== Please let me know if you have any questions or concerns about this IP transition. Regards, -- - DongInn

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[spirit][testing] ICE in gcc 4.8.2 in tests
by Andrey Semashev 07 Apr '14

07 Apr '14

Hi, I'm seeing ICE in a test on BP x86_64 C++11: http://www.boost.org/development/tests/develop/developer/output/BP%20x86_64… This seems to be happening only in develop. I cannot reproduce this with my local gcc 4.8.1. Does anyone know what could be the problem?

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[integer] Is BOOST_HAS_INTPTR_T documentation missing?
by Mostafa 06 Apr '14

06 Apr '14

Is BOOST_HAS_INTPTR_T documentation missing in Boost.Integer?

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[containers] Vector-like container, which takes O(log(N)) > for insert/erase, question to Adam Wulkiewicz about iterators
by Alexander Kuprijanov 06 Apr '14

06 Apr '14

Hi, again, Adam! > > Date: Sat, 05 Apr 2014 16:59:18 +0200 > From: Adam Wulkiewicz <adam.wulkiewicz(a)gmail.com> > And I strongly dissagree with the statement that your container should > be the first choice. std::vector<> will outperform it in most of the > real-life use-cases. Vector outperforms it only (roughly) 2 times on small arrays (when it contains only one leaf) on all operations, only (roughly) 3 times on iterating access on all sizes and only log(N) times on random access. But it severely (N/log(N)) outperforms vector in all insert/erase cases. See my explained test results. I still believe it's close to first choise. > Also, IMHO the most important feature of std::list<> is insert() and > erase() not invalidating other iterators. AFAIU in your container > iterators may be invalid after insert()? That is very interesting question. Currently such sort of persistent iterators (I call them bookmarks) are not implemented. PLEASE PLEASE PLEASE, EVERYBODY, give me an example of the task when such iterators are necessary. Will this feature add feature to my container, if implemented? Best regards, A.K.

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[container] Vector-like container, which takes O(log(N)) for insert/erase, response to Adam Wulkiewicz about performance
by Alexander Kuprijanov 06 Apr '14

06 Apr '14

Hi, Adam! > Date: Sat, 05 Apr 2014 16:59:18 +0200 > From: Adam Wulkiewicz <adam.wulkiewicz(a)gmail.com> > Again, the times you measure are too small to reasonably tell which one > is faster. You could perform each test 10k more times to keep the > results around 1s. I believe my calculations are reliable. I'm sorry I did not explained it earlier and did not provide clarification on github. Firstly, the output is time per one operations in milliseconds. E.g., if it says 1.00e-4, it means 1e-7 seconds or 0. 000 000 1 seconds per one operation. The operation performed many times and result is divided. Secondly, in each operation there are many calculations, by both repeating and array growing. If the line before array says "averaged on 500 measurements" and in array size is 1024, it meant that it was 500 arrays and each of them growed from 512 elements to 1024 elements, giving 256000 atomic additions. Each of them took 1.17e-04 ms in average, they all took about 30 ms. Granularity of Linux timer (which is used in test) is 1 ms, so tolerance in the case is 3%. > Instead of comparing it with a different implementation I guess it would > be sufficient to contain only 2 children in the internal nodes. > Well, I in fact found that numbers 14/28 are near optimum. (There are several optimums for different operations.) Theory agrees with practice, the best performance is when leaf/branch fits one cache line. (In fact, my container allows minimum L=4 M=4, each branch and leaf may have from 2 to 4 items. It behaves worse generally.) I tried to compare it with rope because I was asked to do so. I'll compare it with other similar containers as well. Rope has other problems such as balancing when critical and so on. Best regards, A.K.

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Proposal: Vector-like container, which takes O(log(N)) for insert/erase, response to Bjorn Reese about copy-on-write
by Alexander Kuprijanov 06 Apr '14

06 Apr '14

> Date: Fri, 04 Apr 2014 19:24:53 +0200 > From: Bjorn Reese <breese(a)mail1.stofanet.dk> > To: boost(a)lists.boost.org > Subject: Re: [boost] Proposal: Vector-like container, which takes > O(log(N)) for insert/erase (Glen Fernandes) > Message-ID: <533EEAE5.2040304(a)mail1.stofanet.dk> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > On 04/04/2014 02:10 PM, Lars Viklund wrote: > >> As for the Copy-on-Write semantics, isn't the general consensus that CoW >> is a horrible horrible thing and is very hard to get right+fast in the >> modern world with concurrency? > > Yes: > > http://www.gotw.ca/publications/optimizations.htm > Hi, Bjorn, 1) Proposed Copy-on-Write (CoW) optimization will be only option. Developer will chose, which container he or she wants: a) without CoW, b) with CoW with internal locks, c) with CoW without internal locks (very dangerous). Option "a" will be the first choise. Option "c" is used either in single-threaded apps or if he/she knows that all shallow copies are maintained in the single thtread or behind single semaphore which protects all shallow copies. 2) The article states mostly that there are ineffective optimizations of CoW. CoW by itself is not that bad. Citation: Plain 1726ms Plain_FastAlloc 642ms COW_Unsafe 1629ms COW_AtomicInt 1949ms COW_CritSec 10660ms COW_Mutex 33298ms e.g., the AtomicInt is 10-15% slower than plain, while Mutex 33 times. 3) There are situations where it's worth. Firstly, mobile/embedded devices are memory greedy. Secondly, small changes in very large arrays, such as text editors. Thirdly, no need to implement "undo" command in text editors, that reduces development time. But I see that community does not appreciate this feature so I do it in the end of my priority list. Best regards, A.K.

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[git] Near future.. How do we deal with git-native libraries?
by Rene Rivera 05 Apr '14

05 Apr '14

As the owner of the Predef library which exists originally in github and not svn.. I'm wondering about some things for the near future (as in this coming week): 1. Where will the git repo live for a library? Will the repo need to stay in the boostorg organization? Or is it possible/desirable to use the existing repo that's part of my user account? 2. I notice that there's a ".gitattributes" file in the svn imported version of the Predef repo. Will I need to add that file to my actual Predef git repo? And if so, is there a single canonical version of that file I should use? And a followup.. In the future if that file changes, does it need to change for all repos consistently? Rene. -- -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim - grafikrobot/yahoo

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[asio] Bug: Handlers execute on the wrong strand.
by Greg Barron 04 Apr '14

04 Apr '14

Hi All, I would like to refer you to this bug report: https://svn.boost.org/trac/boost/ticket/9203 I won't paste the full contents of the bug report into this message. The executive summary is that the allocation algorithm for the implementation of asio::strand can and does allocate the implementation of an existing strand to strands that are subsequently allocated. This can have the effect that handlers wrapped in strand (b) will actually be executed on strand (a). I consider this to be a bug but if there is something that I'm misunderstanding about the operation of strands it would be great if you could help me clear it up. If the consensus is that this is a bug, what are the chances for it to be included in the 1.56 release? It is probably too late to be included in the 1.55 release. I've implemented a work around which could only be described as a hack and would be embarrassed to show it to anybody. But it gets me over my hump :). Thanks! -- Greg

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Re: [boost] Proposal: Vector-like container, which takes O(log(N)) for insert/erase (Glen Fernandes)
by Alexander Kuprijanov 04 Apr '14

04 Apr '14

Hi, again, I've implemented a container which should replace vector and have O(log(N)) for insert/delete. Please review. https://github.com/alexkupri/array/blob/master/description/description.txt The code is small, the description is verbose. Best regards, A.K.

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Boost.asio avoid the use of pipe
by Thomas Heller 03 Apr '14

03 Apr '14

Hi list, I'm currently trying to get a asio based software to run on CNK (a very lightweight kernel) which only implements a subset of the POSIX functions. One of the functions which is not implement is pipe. However, asio uses this in the epoll and select reactor. Is there any possibility to avoid that pipe is used? What options do I have? Cheers, Thomas

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[typeof] failed to compile under dependent context
by feverzsj 03 Apr '14

03 Apr '14

hi, list here is some code failed to compile with msvc9. Not sure if it is wrong use case or bug. template<class T> struct A { static T apply() { return T(); } }; template<class T> struct B { typedef BOOST_TYPEOF_TPL(A<T>::apply()) type; // error C2064: term does not evaluate to a function taking 0 arguments }; template<class T> BOOST_TYPEOF_TPL(A<T>::apply()) foo2() // error C2064: term does not evaluate to a function taking 0 arguments { } template<class T> void foo1() { BOOST_TYPEOF_TPL(A<T>::apply()) t; // ok } Regards, zsj -- View this message in context: http://boost.2283326.n4.nabble.com/boost-typeof-failed-to-compile-under-dep… Sent from the Boost - Dev mailing list archive at Nabble.com.

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Boost.Geometry selected for MySQL
by Barend Gehrels 03 Apr '14

03 Apr '14

Hi, Recent news which is published this week (actually today): Boost.Geometry will be used for MySQL 's spatial database features. http://mysqlserverteam.com/building-mysql-with-boost/ This also means MySQL (server) will now use Boost libraries from now on. Regards, Barend

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