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[LibrariesUnderConstruction] new LibrariesUnderConstruction wiki page
by vicente.botet 07 Dec '08

07 Dec '08

Hi, I have created a new wiki page containing some of the libraries under construction for Boost. You can access this page from the Boost Trac wiki https://svn.boost.org/trac/boost/wiki > Projects > Libraries Under Construction or directly https://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction The contents of this page is by nature incomplete and outdated. Please help to maintain this page updated by modifying it directly (if you have the rights) or posting on the Boost mailing lists boost-AT-lists.boost.org or boost-users-AT-lists.boost.org with the prefix [LibrariesUnderConstruction]. If you're the author of one of these libraries and desire that all or part of the information related to your library be removed or modified, please send a mail or you can do it directly if you prefer. If you're a library author and plan on submitting a library but don't know when it will be ready for review, and you want to include your library in this list, please add it directly (if you have the rights) or send a mail. If you're a library author and plan on submitting a library for review in the next 3-6 months, email Ron Garcia or John Phillips ("garcia at osl dot iu dot edu" and "phillips at mps dot ohio-state dot edu" respectively) a short description of your library and they will add it to the Review Wizard Report Libraries Under Construction section. HTH, Vicente

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Mac 64/32 bit universal libraries
by Neal Meyer 07 Dec '08

07 Dec '08

I'm trying to build a 64/32 bit universal application that uses boost. Is there a way to build a version of the boost libraries for this usage?

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Compiling Boost 1.36.0 for Itanium
by Amit Sonawane 07 Dec '08

07 Dec '08

Hi, I have the following environment: WinXP SP2/Visual Studio Team System 2005/Itanium cross compiler tools 1 . Generate boost libs using Itanium cross compiler command prompt with these options bjam -a --build-type=complete --toolset=msvc architecture=ia64 --stagedir=Winia64 stage 2. Compiling under Itanium configuration in VS2005 generates several linker errors as: error LNK2019: unresolved external symbol ._interlockedbittestandset referenced in function "[Entry] bool __cdecl boost::detail::win32::interlocked_bit_test_and_set(long *,long)" (.?interlocked_bit_test_and_set@win32@detail@boost@@YA_NPEAJJ@Z) error LNK2001: unresolved external symbol ._interlockedbittestandset 3.The projects compile fine under x86 and x64. _interlockbittestandset is not intrinsic on Itanium platform Has anyone come across this before ? or what is the correct way to build boost under itanium cross platform other then the options I used. Cheers, Esta mensagem pode conter informação confidencial e/ou privilegiada. Se você não for o destinatário ou a pessoa autorizada a receber esta mensagem, não deverá utilizar, copiar, alterar, divulgar a informação nela contida ou tomar qualquer ação baseada nessas informações. Se você recebeu esta mensagem por engano, por favor avise imediatamente o remetente, respondendo o e-mail e em seguida apague-o. Agradecemos sua cooperação. This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose, change, take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation.

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Threads and linking against the right Boost-libs
by Christoph Duelli 07 Dec '08

07 Dec '08

* When I have a program that use a second thread and only that second thread does use Boost, will I need to link against the "-mt" libs? (I am using linux.) [An example would be: when I use some Boost facilities together with Qt: Qt4 creates threads even if I do not use any explicitly.] * If I create a lib and that lib does not use threads, but does use Boost.Regex, I usually add a "-lboost_regex" to that lib. If a program later on uses both my lib and threads, would I have had to link against boost_regex-mt? Does this boil down to 'if I might use threads I should always link against the -mt libs'? Best regards Christoph

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Re: [Boost-users] [review][constrained_value] Review of Constrained Value Library begins today
by Jesse Perla 06 Dec '08

06 Dec '08

One idea on the dynamically changing the global bounds for a type as I keep mentioning, one concern people have is that it could invalidate instantiated objects of the type. As I said before, being able to dynamically change the bounds at runtime is essential, but most of the time you would do it before you instantiate anything. Hence, one solution is to make a check to see if it has been instantiated yet. I don't know enough metaprogramming to know if this is possible, but the idea is to flip some kind of a compile time flag in the constructor of the type and if you try to change the bounds after that, it fails a compile time assertion. So, the following would work: typedef bounded_type<double, "INTEREST RATE"> interest_rate; interest_rate::change_bounds(.8, .99); interest_rate r = .95; But the following would fail at compile time: typedef bounded_type<double, "INTEREST RATE"> interest_rate; interest_rate r = .95; interest_rate::change_bounds(.8, .99); If this is a good idea, my only request is a preprocessor instruction to turn it off... -Jesse

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ublas vector resize std::bad_alloc
by Fabian Lim 06 Dec '08

06 Dec '08

Im having a memory management problem. I have 2 ublas vectors Vector A = vector<V1 > Vector B = vector<vector<V2 > > : first vector level size is 2^22 where the data types both V1=vector<int> and V2 are vector<vectors<int>> and the size |V1| <= 2 and the first level size of V2 <=2 and the second level size <= 10. A grows as my program runs. B also grows but only the second level. I run in windows and when i check the memory usage, it seems to be around 90,000K when the exception throws. I dont really have a good feel for these figures, so I compared to my firefox browser, which seems to occupy approximately the same amount of memory, hence i concluded that not alot of memory is used. My computers have around 1/2 Gb RAM. I do not see the typical OS slowdown which accompanies alot of paging.

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boost::thread issue
by danielsabin＠comcast.net 05 Dec '08

05 Dec '08

Hi, I started working on a project a couple of months ago and i decided to use boost::thread. I like the library, very nicely done and easy to use - great job. However, I ran into an issue and although i have already spent a significant amount of time trying to figure it out, I was not able to make any progress so far. The project is written in pure C++ (no managed code) on Windows XP/SP3. I am using Visual Studio 2005 with SP1 as the C++ compiler. I am using the pre-built binaries for boost 1_36_0 provided by boost consulting. My main program simply creates several boost::thread objects which do various things. Everything works fine except for one thing: occasionally when I start the program I receive the following error: "The exception unknown software exception (0xc0000409) occurred in the application at location 0x00421cd3". In general exception 0xc0000409 means that the system detected (or thinks it detected) an overrun of a stack-based buffer. The code is compiled with the /GS switch (Buffer security check) enabled. The debug stack trace when the exception is thrown shows 2 threads, the exception being thrown by thread2, as follows: (thread 1) 5752 __tmainCRTStartup __CxxSetUnhandledExceptionFilter Normal 0 --------------------------------------------------------------------------------- ntdll.dll!_KiFastSystemCallRet@0() ntdll.dll!_ZwWaitForSingleObject@12() + 0xc bytes ntdll.dll!_RtlpWaitForCriticalSection@4() + 0x8c bytes ntdll.dll!_RtlEnterCriticalSection@4() + 0x46 bytes ntdll.dll!_LdrLockLoaderLock@12() + 0x6b bytes kernel32.dll!7c80b43f() [Frames below may be incorrect and/or missing, no symbols loaded for kernel32.dll] ntdll.dll!_ZwQueryVirtualMemory@24() + 0xc bytes kernel32.dll!7c80b9ed() kernel32.dll!7c8638bd() kernel32.dll!7c8449b0() ntdll.dll!_RtlpAllocateFromHeapLookaside@4() + 0x31 bytes kernel32.dll!7c80262a() ntdll.dll!_NtQueryInformationProcess@20() + 0xc bytes msvcr80.dll!7814a84c() MyService.exe!__CxxSetUnhandledExceptionFilter() Line 90 C++ msvcr80.dll!78131762() > MyService.exe!__tmainCRTStartup() Line 494 + 0xf bytes C kernel32.dll!7c817007() ntdll.dll!_RtlpAllocateFromHeapLookaside@4() + 0x31 bytes (thread 2) 7976 __report_gsfailure __report_gsfailure Time Critical 0 ------------------------------------------------------------------------- MyService.exe!__crt_debugger_hook() Unknown > MyService.exe!__report_gsfailure() Line 298 + 0x7 bytes C MyService.exe!boost::detail::create_once_mutex() + 0x63 bytes C++ MyService.exe!boost::call_once<void (*)(void)>() + 0x36 bytes C++ MyService.exe!boost::`anonymous namespace'::run_thread_exit_callbacks() + 0x34 bytes C++ MyService.exe!boost::thread::interrupt() + 0xdc bytes C++ ntdll.dll!_LdrpCallInitRoutine@16() + 0x14 bytes ntdll.dll!_LdrpCallTlsInitializers@8() + 0x12fad bytes ntdll.dll!_LdrShutdownThread@0() + 0xf4ae bytes kernel32.dll!7c80c0c6() [Frames below may be incorrect and/or missing, no symbols loaded for kernel32.dll] csauser.dll!10103b7f() kernel32.dll!7c80b6b9() Since I did not get too far on my own I really need your help. Did anybody else run into anything similar or does anybody have any idea about how to debug this? Thanks, --daniel

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[lambda] Can't quite get the hang of it!
by Robert Jones 05 Dec '08

05 Dec '08

Starting with this... for( j = joff; j < joff + 8; j++) for( i = ioff; i < ioff + 8; i++) img->m7[j][i] = iClip1(img->max_imgpel_value, (img->m7[j][i]+(long)mpr[j][i])); I'd like to move as much of the loop invariance out of the loop as I can. So I tried this... using boost :: lambda :: _1; using boost :: lambda :: _2; int ilast = ioff + 8; int jlast = joff + 8; boost :: function< int( int &, int ) > clip = _1 = boost :: lambda :: bind( iClip1, img -> max_imgpel_value, _1 + _2 ); for( j = joff; j != jlast; ++ j ) for( i = ioff; i != ilast; ++ i ) clip( img -> m7[j][i], mpr[j][i] ); Which works, but I'd like the nested clip function to be fn( i, j ), so I tried this... boost :: function< void( int, int ) > clip2 = boost :: lambda :: bind( clip, img -> m7[ _2 ][ _1 ], mpr[ _2 ][ _1 ] ); for( j = joff; j != jlast; ++ j ) for( i = ioff; i != ilast; ++ i ) clip2( i, j ); Which doesn't work. I think I need some boost::refs around the arrays I'm subscripting, but I can't quite seem to get it right. Error is... loop.cpp:50: error: no match for 'operator[]' in 'img->img_par::m7[boost::lambda::<unnamed>::_2]' loop.cpp:50: error: no match for 'operator[]' in 'mpr[boost::lambda::<unnamed>::_2]' loop.cpp:50: error: `bind' undeclared (first use this function) Any thoughts? Thanks, Rob.

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shared_ptr to stack-allocated object
by Jason Cipriani 05 Dec '08

05 Dec '08

I'm refactoring parts of an existing application to use shared_ptrs instead of raw pointers. What is the best way to deal with code like this (please note in this situation passing a pointer to a stack-allocated object to function is acceptable and safe): void function (shared_ptr<Object> ptr) { ... } void function2 () { Object o; function(&o); // <--- need to change this } It seems I have two choices, I am not sure which is better, or if there are other common techniques. I can either use a no-op delete function: void noop (Object *) {} void function2 () { Object o; function(shared_ptr<Object>(&o, noop)); } Or I can allocate it on the heap instead of the stack, and let shared_ptr deal with the cleanup (this seems to be the more convenient solution): void function2 () { shared_ptr<Object> o(new Object); function(o); } What's the normal practice here? Thanks, Jason

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Re: [Boost-users] [review][constrained_value] Review of Constrained Value Library begins today
by jesseperla＠gmail.com 05 Dec '08

05 Dec '08

Robert: >Sorry, but this makes no sense to me in the context of constrained values. If >the current bounds are [0, 1] and you have r1 == .5 and r2 == .9, then what >changing the bounds for the whole type to [.8, .99] would mean for r1? How the >type is supposed to know that there is an instance that is not valid according >to the new bounds? The type should keep handles to all its instances? Or the >bounds should change anyway, leaving the instance in invalid state? So what >would be the point of bounds checking, if you can't guarantee that once you >assign a valid value then the object will remain valid? The problem for me is that the change_bounds function at runtime operators on an instance rather than for the type itself (which is what the compile time bounds mean, and what I really want). I was using this as an example of why I believe the semantics are different and what I really want is something like what I listed next: >typedef bounded<double, "INTEREST RATE"> interest_rate; >typedef bounded<double, "RISK_AVERSION"> risk_aversion; >interest_rate r; >risk_aversion crra ; >change_bounds(r, .8. .99); //Statically change it >change_bounds(crra, .5, 10); //Statically. >interest_rate r_guess; //want the right bounds But even this is a little shady since I kept the change_bounds called on an instance to show the similarity to what is listed. What I would really be looking for is a way to change the bounds for the type itself, which would change static bounds. Maybe something like the following: >typedef bounded<double, "INTEREST RATE"> interest_rate; interest_rate::change_bounds(.8, .99); //Changes static data for the type? Does that help you make sense of my previous questions and comments? Now, you may say that this doesn't work because how could it throw errors on existing variables of type interest_rate that may not fulfill the bounds? The short answer is that it couldn't and it doesn't matter. In practice, you are changing the bounds here prior to creating instances of an item. It is purely a question of being able to dynamically create bounds for a type and then query them later... this makes the library far, far more than just a debugging and bounds checking utility and gives real semantics that can better match mathematics. >What you ask for is not possible in C++. You cannot have one type and use it >exactly the same way as other type. I'll give you some examples (having >constrained<string> cs): > const char * s = cs.c_str(); // not possible >Type constrained<string> can't have members that string has. > char c = cs[0]; // not possible Yes, I see now why it can't work for wrapping classes. But in my mind I am only thinking of the wrapping of intrinsic, built in types like doubles and ints. Here I would never want to call member functions on them... But it sounds like with no implicit conversions for template instantiation, we could run into problems... But how often would this be in practice? My knowledge of generic programming is not sufficient to understand the story here, but it sounds like the problem with std::max is that it is forcing the two parameters to be of the same type and that is the failure. Otherwise if std::max was written to take two different types with compatible comparison operators, that this could work fine? And if the constrained_value<double> had an implicit conversion to double, then we would have no problem? So is std::max anomalous here, and this wouldn't come up in practice for most usage for most numeric work? Thanks Robert. I really like this library and think it has great promise for those of us programming mathematics written on a blackboard.

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