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Re: [boost] Proposal to add smart_ptr to the boost library
by David Maisonave 31 Jan '06

31 Jan '06

"Peter Dimov" <pdimov(a)mmltd.net> wrote in message news:<010a01c6265b$27cd4040$6507a8c0@pdimov2>... > David Maisonave wrote: > > > Since the current smart_ptr (policy_ptr) class at boost vault is on > > hold, I like to propose adding the following smart_ptr class to the > > boost library: > > > > http://code.axter.com/smart_ptr.h > > smart_ptr& operator=(const smart_ptr& Src) > { > if (m_type != m_type) > { > Src.lock(); > m_ownership_policy.assign(m_type, m_clone_fct, Src.m_type, > Src.m_clone_fct, Src.m_ownership_policy, m_ownership_policy); > Src.unlock(); > } > return *this; > } > > You need a unit test. ;-) Yep. You're absolutely correct. This is also why I wasn't able to duplicate the cycle refernece leak, similar to boost::shared_ptr. I seem to have thrown this bug in, when I was adding lock() logic. I've added a unit test for this specific logic. I still have plenty more to go. Thanks

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Re: [boost] Why does shared_ptr have a public reset() method
by David Maisonave 31 Jan '06

31 Jan '06

"Peter Dimov" <pdimov(a)mmltd.net> wrote in message news:<00f101c62659$d1264990$6507a8c0@pdimov2>... > David Maisonave wrote: > > It's not used internally, so there is no need to make it private. > reset() is > a simple shorthand for swapping your shared_ptr with a temporary > default-constructed one, then destroying the temp. You can also achieve the > same effect by assignment. > > p = shared_ptr<T>(); // same as p.reset() Reading the weak_ptr introduction gave me a misunderstanding of what reset does. I thought reset just release the pointer without deleteing it if it was the last referenced. If it does delete it when it's the last reference, than it does make sense to have it public. > Don't tell me that your smart pointer doesn't support assignment. :-) It not only supports assignment, but it also has the ability to assign to a different policy type. > There is no single canonical use for weak_ptr. It's a versatile tool > that > can be used in every situation that matches the above description. Some > people use for it to break shared_ptr cycles. I just ran a test on this, and it seems that boost::shared_ptr does result in leaving memory leak in cycle logic. However, when I tested my proposed smart_ptr, it does not have this problem. It's able to correctly destroy the objects even in cycles. The proposed boost::policy_ptr also has the same cycle problem like boost::shared_ptr. I don't understand why they're not able to resolve this in the destructor call. Either I'm missing something in my smart_ptr, or there's some extra wacky logic in the boost::shared_ptr that's blocking deletion in cycles. (Which I don't get)

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[Boost-bugs] [ boost-Bugs-1420498 ] Bundled graph properties
by SourceForge.net 31 Jan '06

31 Jan '06

Bugs item #1420498, was opened at 2006-01-31 08:49 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1420498&group_… Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: graph Group: None Status: Open Resolution: None Priority: 5 Submitted By: Douglas Gregor (dgregor) Assigned to: Douglas Gregor (dgregor) Summary: Bundled graph properties Initial Comment: Bundled properties are supported for vertex and edge properties but not graph properties. Fix it! ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1420498&group_… ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ Boost-bugs mailing list Boost-bugs(a)lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs

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Fw: Re: [regex]using boost::regex with STLport 5.0 on VS.net
by Wang Weiwei 31 Jan '06

31 Jan '06

Hello, I think there would better be a way to prevent other people - as stupid as me :) - from making the same low-level mistake. The posible solution may be a check of the STLport macros in building with STLport toolsets. Thanks again. Max > > > sorry, the error msg is: > > > > > > BoostTest.obj : error LNK2019: missing symbol "void __cdecl > > > boost::re_detail::raise_runtime_error(class _STL::runtime_error > > > const &)" > > Errors like this usually arise either because: > > 1) You haven't defined __STL_DEBUG when building a debug build (the prebuilt > lib's do this so you have to in order to link to them). However if this is > the case you should have got a #error from the autolinking code telling you > of the problem. YES, I have defined the __STL_DEBUG macro for the debug build. > 2) You're build of Boost did not in fact get built against STLport. Try > taking a peek at the symbols defined in the libraries to see if they're > using _STL or _STLD names (from STLport) or std:: names (from VC++). Also > try building with bjam and the -d2 option so you can see the command lines > generated and verify that all the paths are in fact correct. GREAT! That really helps. Using a text editor, I cannot find _STL or _STLD names in a should-be STLport linked lib, but I can find "std"! Everything gets ok after I adding 2 lines into the build batch file: SET INCLUDE="D:\STLport_50\stlport";%INCLUDE% SET LIB="D:\STLport_50\lib";%LIB% Thank you so much! > > John. > > > _______________________________________________ > Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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Patch for slist-related regression errors
by Janusz Piwowarski 31 Jan '06

31 Jan '06

Hi Mingw (gcc >= 3.1.0) has slist in ext subdirectory. I used a workaround I found in boost/config/stdlib/libstdcpp3.hpp . Regards, Janusz

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Proposal to add smart_ptr to the boost library
by David Maisonave 31 Jan '06

31 Jan '06

Since the current smart_ptr (policy_ptr) class at boost vault is on hold, I like to propose adding the following smart_ptr class to the boost library: http://code.axter.com/smart_ptr.h IMHO, the above class has more functional features, than the class in the boost vault, and the class is ready for use. The smart pointer is very exchangeable with each other, and it has easy to use policy options. It has an optional lock policy that can be used on all three main ownership policy types (deep_copy, COW, & Shared). It has three methods of cloning policies that can give different levels of generic coding and/or slicing avoidance. The shared and COW policy, can use reference-count, reference-link, and reference-intrusive polices. In my performance test, the shared and COW policies along with reference-link policy, are able to out perform the boost::shared_ptr. It can be used with non-compliant compilers like VC++6.0 and Borland BCC55. And on more compliant compilers (VC++7.x, 8.0, GNU 3.x, 4.x), it has additional capabilities, which allows it to be exchangeable with different policy types, and derive types (T). Like boost::week_ptr, the smart_ptr supports value (pointee) comparison semantics, so it can be used in an associated container like std::map and std:set. Unlike the boost pointer containers, this smart pointer can be used as the first type in the std::map container. The smart_ptr can be used as a shared-pointer, clone smart pointer, Copy-On-Write pointer, and a synchronized smart pointer. Since there's already a similar class in the boost vault, that indicates that there's already interest in this type of class. So IMHO, the question really should be, should we continue to wait for a class in the vault that might never get completed, and might not have all the functionality available in the above smart_ptr? Or should this class be pushed through in parallel to the current vault policy_ptr class. To see a validation test, and performance test, use the following code: http://code.axter.com/boost_ptr_containers/main.cpp http://code.axter.com/smart_ptr.h http://code.axter.com/shape_test.h http://code.axter.com/copy_ptr.h http://code.axter.com/cow_ptr.h

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Re: [boost] Proposal to add smart_ptr to the boost library
by David Maisonave 31 Jan '06

31 Jan '06

"David Abrahams" <dave(a)boost-consulting.com> wrote in message news:<8764o1azuq.fsf(a)boost-consulting.com>... > "David Maisonave" <dmaisonave(a)commvault.com> writes: > >> IIUC, the thread-safety problem with reference-linked > >> implementation > >> isn't that so much that it's hard to achieve -- anyone can use a > >> shared mutex -- it's that it's hard to make a thread-safe > >> implementation efficient. That is to say, you pay for the cost of > >> locking and unlocking a mutex, and there's no way around it (**). > >> Locking and unlocking mutexes is way more expensive than performing > >> the lock-free operations used by boost::shared_ptr. > > > > That's true. But it's been my experience that the majority of > > development don't have objects access via multiplethreads or don't > > run in a multithread environment. In this environment, you're paying > > additional price for using boost::shared_ptr reference-count logic, > > but not getting any benefits from it. > > Not if you're compiling without mt support on; the thread safety > features of shared_ptr just compile away (and I think there's a macro > you can use to force them off). Let's compare apples to apples: your > reflinked implementation will be slower in a MT environment. I'm not > yet convinced it will be faster in a ST environment unless you leave > the MT features of shared_ptr turned on. Currently, my test results don't support your above comment. Please provide the this macro you're referring to. Without this macro, there's no way of testing your claim.

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Why does shared_ptr have a public reset() method
by David Maisonave 31 Jan '06

31 Jan '06

Why does boost::shared_ptr have a public reset() method? Why is this method not private? In reading the introduction for weak_ptr, it seems like its main purpose is to cover up or control this opening to boost::shared_ptr. http://www.boost.org/libs/smart_ptr/weak_ptr.htm If boost::shared_ptr didn't have this type of public access, would there be a need for the weak_ptr? I can not find any example code that would justify the requirement for the weak_ptr other than the code in above link.

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msvc, vc-7_0
by Arkadiy Vertleyb 31 Jan '06

31 Jan '06

Hi all, I can't see a column for one of these compilers even in the full regression view... Does anyone still care to support them? Does anyone care if typeof supports these compilers? Regards, Arkadiy

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Re: [boost] Serialization and disctintion between eof and end of archive
by Oliver.Kowalke＠infineon.com 31 Jan '06

31 Jan '06

>OK, after further investigation it appears that the archive reader is in >fact sensitive to one of these two: > >- end of line >- end of stream Hmmm - I didn't notice the end-of-line issue. Now it works. Please ignore my previous email. Regards, Oliver

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