November 2006 - Boost-users - lists.preview.boost.org

Errors compiling Boost.Python library on Solaris
by chris botos 15 Nov '06

15 Nov '06

Hi, I'm new to this list and to Boost. I'm interested in using Boost to wrap C++ objects in Python. The environment is Solaris 10, x86. I did the following: Downloaded boost_1_33_1.tar and extracted it to /opt/boost. >setenv PYTHON_ROOT /usr/local > cd to /opt/boost/boost_1_33_1/libs/python/build > bjam I get lots of error messages, repeated throughout the compile and tend to be grouped and refer to the same line: '->' cannot appear in a constant-expression '&' cannot appear in a constant-expression template argument 1 is invalid value is not a member of '<declaration errors>' ...failed gcc-C++-action ... is also associated with the above If I "bjam" from /opt/boost/boost_1_33_1, I get the same errors when it gets to the python library. I would most appreciate any help with this! Regards, Chris Botos

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comparing map's key and sorted vector
by Maitre Bart 15 Nov '06

15 Nov '06

Suppose I have a map (m) and a sorted vector of strings (v). The map's key is a string, and the map's value is foobar. I wish to compare map's keys with the vector's values and detect if they all match: (*mit).first == *vit and wish to do it with STL/Boost algo and functors. So I am starting with this: equal(m.begin(), m.end(), v.begin(), boost::bind(std::equa_to<string>(), std::select1st<std::pair<string,foobar> >(_1), _2)); I know 2 parameters are past to bind: *mit and *vit . However, before the equality, I want to extract the key from the map iterator (i.e. (*mit).first) before the comparison. That is this part I have difficulty to concretise. Btw, is there any equivalent to select1st (SGI extension) in Boost? Does anyone have any idea? I must be close to the solution...

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[OT] Strange Subject Line Problem with this Mailing List
by Wu Yinghui, Freddie 14 Nov '06

14 Nov '06

Hi all, Sorry for this post, as it is not related to Boost, but to this mailing list instead. I've been seeing subject lines in a mess for "Re:" posts as illustrated below: ==== snip ==== > Today's Topics: > > 1. BGL: Bundled Properties in subgraphs (Greg Reynolds) > 2. Re: [Serialization] a couplacrashesfromhiearchycomplexity > (Reusser, Edward) ==== snip ==== As seen above, the subject line of the second post was unreadable to me without spending a fair amount of efforts. Has anyone checked out what was the cause of this problem yet? Cheers, Freddie -- Wu Yinghui, Freddie Research & Development Senior Software Engineer Volume Interactions Pte Ltd 1 Kim Seng Promenade, #12-01 Great World City East Tower Singapore 237994 Tel: +65 62226962 (Ext 216) Fax: +65 62226215 Email: yhwu(a)volumeinteractions.com URL: http://www.volumeinteractions.com Important: This message is intended for the recipient(s) addressed above. It contains privileged and confidential information. If you are not the intended recipient, please notify the sender immediately by replying to this message and then delete it from your system. You must not read, copy, use, or disseminate this communication in any form. Thank you.

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[serialization] Richer "tagged" fields and polymorphic archive types
by Caleb Epstein 14 Nov '06

14 Nov '06

Robert, First let me start off by thanking you for the excellent Boost Serialization library. I'm planning to use it as part of a new system I'm building at my place of work as a more flexible replacement for Rogue Wave's "saveGuts/restoreGuts". I've been able to implement my own archive types without too much of a struggle, and have been overall very impressed with the functionality of the library and its documentation. Now some background and then on to the questions :) I'm not sure if you are familiar with TIBCO's "Rendezvous" messaging middleware product (http://tibco.com/) or with the FIX protocol (http://fixprotocol.org/) but these are both commonly used in financial services applications. Rendezvous as a messaging transport and FIX as a general message convention and data dictionary. FIX also specifies a "session" layer used for communication, but thats out of scope here. Both Rendezvous (RV) and FIX support the concept of numeric field identifiers in their messages. In FIX, serialized messages look like TAG=VALUE\x01TAG=VALUE\x01... where TAG is an integer field ID and VALUE is the value associated with that tag and \x01 is an ASCII SOH character. In RV messages, fields may be given a name and/or an integer field ID. So it is pretty straightforward to represent a FIX message as an RV message (or vice-versa) if you always use these numeric IDs. Also, these "tagged" message formats facilitate interchange of data between different systems because they do not place stringent requirements on field ordering or even field presence in some cases. In the system I'm working on, the fundamental object types can all be mapped more or less directly to messages in the FIX specification. OK, so now onto the meat of the question. What I'd like to use in this application is something akin to NVP serialization for my objects, but which I'll call FIELD serialization. Every member of an object can be associated with a FIELD ID which would contain both a name and an integer ID (e.g. "Price" and 44). The universe of field IDs is more or less static and well-known. To this end I've created two utility classes called field_id and field. The field_id class is a std::pair<int, const char*> and the template field class is a std::pair<const field_id*, T*> not unlike the nvp class. It provides methods to get the field's name, id, and value. There is also a template utility function "make_field(const field_id&, T&)" that creates a field object in the same way "make_nvp" creates an nvp. I have implemented a "tibco_oarchive" that provides a template "save_override(const field<T>&, int)" method, and this works fine if I am using template<typename Archive> serialization methods with my archive definition in scope, and if I write my serialization code using "make_field" instead of "make_nvp". But this, naturally, does *not* work if I try to use polymorphic archives, since the base classes here do not know anything about my "field" template, only "nvp". Additionally, my template-based serialization code will fail to compile with archive types that don't provide "save_override"s for my "field" template, which is all of the "standard" archive classes. What I'd like is to figure out some way to implement this tagged-field serialization scheme in a way that would be compatible with the polymorphic archive interface and that would (ideally) still compile with the existing archive implementations that don't know about my "field" class. This latter requirement is less important. The reason I'm leaning toward the polymorphic archive interface is that I'm sure we will need to adopt new wire-formats and middleware interfaces in the future. Keeping all the object serialization code in a library that doesn't require recompilation will make this process very easy. So, do you think you could offer any suggestions on how I might go about achieving this? Let me know if you need more information or clarification, and thanks for your help. -- Caleb Epstein

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Sequence of Types, What For?
by Terry G 14 Nov '06

14 Nov '06

I've just finished reading C++ Template Metaprogramming again. I just don't get it. Why would someone use a type container? I have used enable_if, along with some of the logic functions for managing an overload set. Otherwise, I'm clueless. I'd really like a reference to an MPL primer or some case studies. Too much pain with very little gain. Time to ask for help. Rereading this, it sounds negative. Really, I think the MPL is really cool! terry

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Re: [Boost-users] Serialization problem on 64-bit Windows release
by Sergey Filippov 14 Nov '06

14 Nov '06

Robert Ramey <ramey <at> rrsd.com> writes: > This doesn't seem to be the case in your situation. Anyway, thank you for the information. I'll keep trying to reproduce an issue in test lab. Sergey

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Minor ublas issue
by Daniel Krügler 14 Nov '06

14 Nov '06

Hello, I stumbled about the current cvs HEAD version of exception.hpp, where I found one remaining throw under *_NO_EXCEPTIONS conditions in "singular". Here the proposed fix: Index: exception.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/numeric/ublas/exception.hpp,v retrieving revision 1.19 diff -u -r1.19 exception.hpp --- exception.hpp 2 Feb 2006 19:27:23 -0000 1.19 +++ exception.hpp 13 Nov 2006 18:54:27 -0000 @@ -175,7 +175,6 @@ explicit singular (const char *) {} void raise () { - throw *this; std::abort (); } #endif I also would like to recommend, that the current exception text of struct non_real should be changed as follows (The prefix "exception:" seems redundant): Index: exception.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/numeric/ublas/exception.hpp,v retrieving revision 1.19 diff -u -r1.19 exception.hpp --- exception.hpp 2 Feb 2006 19:27:23 -0000 1.19 +++ exception.hpp 13 Nov 2006 19:01:45 -0000 @@ -185,7 +185,7 @@ #if ! defined (BOOST_NO_EXCEPTIONS) && ! defined (BOOST_UBLAS_NO_EXCEPTIONS) // Inherit from standard exceptions as requested during review. : public std::domain_error { - explicit non_real (const char *s = "exception: non real") : + explicit non_real (const char *s = "non real") : std::domain_error (s) {} void raise () { throw *this; Greetings from Bremen, Daniel Krügler

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BJam can't find arguments to gcc-spawn
by Charles Broderick 14 Nov '06

14 Nov '06

I am having problems running even a basic Jamfile consisting only of: Main : main.c ; When running bjam with debugging on, I receive this output (truncated). I looked at allyourbase.jam and gcc-tools.jam, and it looks like OK jam code to me... why won't main.c get passed in as the target? /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:1136:>>>>|>>>>|>> switch .c /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:1139:>>>>|>>>>|>> Cc : main.c /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:624:>>>>|>>>>|>>>> DEPENDS : main.c /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:626:>>>>|>>>>|>>>> Cc-platform-specifics : main.c /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:593:>>>>|>>>>|>>>>|> local _h = /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:634:>>>>|>>>>|>>>> Cc-action : main.c /local/apps/boost/1.33.1/tools/build/v1/gcc-tools.jam:489:>>>>|>>>>|>>>>|> gcc-spawn /local/apps/boost/1.33.1/tools/build/v1/gcc-tools.jam:489: in Cc-action *** argument error * rule gcc-spawn ( targets + ) * called with: ( ) * missing argument targets /local/apps/boost/1.33.1/tools/build/v1/gcc-tools.jam:402:see definition of rule 'gcc-spawn' being called /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:634: in Cc /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:1139: in Object /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:1207: in Objects /local/apps/boost/1.33.1/tools/build/v1/allyourbase.jam:969: in Main Jamfile:2: in load-jamfiles /local/apps/boost/1.33.1/tools/build/v1/bootstrap.jam:21: in boost-build /local/apps/boost/1.33.1//boost-build.jam:16: in module scope

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Re: [Boost-users] [Serialization] a couplacrashesfromhiearchycomplexity
by Reusser, Edward 13 Nov '06

13 Nov '06

Robert, After more analysis, I am getting evidence that this error might be on my end (something seems to corrupt the XML text itself). More to follow... Ed ________________________________ From: Robert Ramey [mailto:ramey@rrsd.com] Sent: Monday, November 13, 2006 2:22 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [Serialization] a couplacrashesfromhiearchycomplexity it would seem to me that a stack trace would be interesting to see. I'm wondering if its just a stack that is too short (I would have expected to see this sooner if it was) or some error somewhere which creates an unterminated recurssion. With VC its easy to see the stack trace. With the Gnu Debuger, one has to back trace from the right point. Robert Ramey "Reusser, Edward" <Edward.Reusser(a)actel.com> wrote in message news:5E916BAE1732F344BAFD713DF2373479016EA233@SV-MSG-01.amer.actel.com.. . Robert, I would need permission to send you the exact library code. I am reluctant to do this primarily because recreating my exact build environment would be a hassle (we are using gnumake on the PC). I also would need to do this directly to you, as I could not post this code into a public forum. Having said that, any recursive descent parser has complexity limits based on stack size. It would be pretty easy to create test cases that probe these complexity limits for the various archive types. I would like to see how much (approximately) stack space is allocated in the runtime for each level of xml hierarchy, and also for the text archives. The main complexity seems to be because I am using shared_ptr's extensively at all levels of the hierarchy. Thus, I have 2 levels nested for each class, the <px> data </px> and the actual data, which is in turn being represented by a collection of shared_ptr's, etc. I am also using std::map of shared pointers, and std::set of shared_ptr's. I also use enable_shared_from_this<T> for my base classes, then statically cast the resultant shared pointers internally for the derived classes. This is to get around a Linux problem which I can describe more fully if you like (would take a few pages of explanation). So for example: class Base : public boost:enable_shared_from_this<Base> { virtual boost::shared_ptr<Base> GetSharedFromThis() { return shared_from_this(); } }; class Derived1 : public Base { public: virtual boost::shared_ptr<Derived1> GetSharedFromThis() { return static_pointer_cast<Derived1>( shared_from_this() ); } }; class Derived2 : public Base { public: virtual boost::shared_ptr<Derived2> GetSharedFromThis() { return static_pointer_cast<Derived2>( shared_from_this() ); } }; I am assuming that I do not need to call boost::serialization::base_object<boost::enable_shared_from_this<Base> >( *this ); When I serialize the base class. Could that be the problem? I think what I am going to do is go back into the program and simply eliminate all of the shared_ptr serializations. I can serialize to raw pointers, and then just create the shared_ptr's from those pointers explicitly in my case. I simply do not ever have any shared_ptr's with multiple reference counts to worry about. I will let you know what happens. ________________________________ From: Robert Ramey [mailto:ramey@rrsd.com] Sent: Monday, November 13, 2006 8:30 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [Serialization] a coupla crashes fromhiearchycomplexity I would be curious to see your particular case. The fact that different archives give problems that seem related to nesting depth suggest along with the fact that this hasn't been reported suggests that there is some sort of use case or error which hasn't been considered. Robert Ramey "Reusser, Edward" <Edward.Reusser(a)actel.com> wrote in message news:5E916BAE1732F344BAFD713DF2373479016EA059@SV-MSG-01.amer.actel.com.. . I am using the serialization library in boost 1.33.1. I am compiling on windows using the VC 7.1 compiler. The problem I am having is that when I use xml_iarchive and xml_oarchive, everything works just fine for simple cases, but if the xml gets very deep ( same exact class hierarchy, just more data organized a little more complexly) I am getting runtime stack overflow crashes in the spirit parser. I figured I could solve that by simply substituting text_iarchive and text_oarchive. Please note that I am simply substituting in these archive types instead of using the xml archive headers, which work. There are no other code changes anywhere. Now I am getting the following compiler error: \boost\mpl\eval_if.hpp(40) : fatal error C1204: compiler limit : internal structure overflow Any suggestions? I can try increasing the stack size of my current application to eliminate the xml runtime stack overflow problem, but I am uneasy doing this until I understand how to calculate the stack sizes required, and why it is happening. Furthermore, I would prefer using the text archives, since the data is more compact than the xml ones. Ed Reusser Principal Software Engineer Actel Corporation (408) 318-4972 ________________________________ The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information. ________________________________ _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users ________________________________ The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information. ________________________________ _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information.

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Re: [Boost-users] [Serialization] a coupla crashes fromhiearchycomplexity
by Reusser, Edward 13 Nov '06

13 Nov '06

Robert, I would need permission to send you the exact library code. I am reluctant to do this primarily because recreating my exact build environment would be a hassle (we are using gnumake on the PC). I also would need to do this directly to you, as I could not post this code into a public forum. Having said that, any recursive descent parser has complexity limits based on stack size. It would be pretty easy to create test cases that probe these complexity limits for the various archive types. I would like to see how much (approximately) stack space is allocated in the runtime for each level of xml hierarchy, and also for the text archives. The main complexity seems to be because I am using shared_ptr's extensively at all levels of the hierarchy. Thus, I have 2 levels nested for each class, the <px> data </px> and the actual data, which is in turn being represented by a collection of shared_ptr's, etc. I am also using std::map of shared pointers, and std::set of shared_ptr's. I also use enable_shared_from_this<T> for my base classes, then statically cast the resultant shared pointers internally for the derived classes. This is to get around a Linux problem which I can describe more fully if you like (would take a few pages of explanation). So for example: class Base : public boost:enable_shared_from_this<Base> { virtual boost::shared_ptr<Base> GetSharedFromThis() { return shared_from_this(); } }; class Derived1 : public Base { public: virtual boost::shared_ptr<Derived1> GetSharedFromThis() { return static_pointer_cast<Derived1>( shared_from_this() ); } }; class Derived2 : public Base { public: virtual boost::shared_ptr<Derived2> GetSharedFromThis() { return static_pointer_cast<Derived2>( shared_from_this() ); } }; I am assuming that I do not need to call boost::serialization::base_object<boost::enable_shared_from_this<Base> >( *this ); When I serialize the base class. Could that be the problem? I think what I am going to do is go back into the program and simply eliminate all of the shared_ptr serializations. I can serialize to raw pointers, and then just create the shared_ptr's from those pointers explicitly in my case. I simply do not ever have any shared_ptr's with multiple reference counts to worry about. I will let you know what happens. ________________________________ From: Robert Ramey [mailto:ramey@rrsd.com] Sent: Monday, November 13, 2006 8:30 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [Serialization] a coupla crashes fromhiearchycomplexity I would be curious to see your particular case. The fact that different archives give problems that seem related to nesting depth suggest along with the fact that this hasn't been reported suggests that there is some sort of use case or error which hasn't been considered. Robert Ramey "Reusser, Edward" <Edward.Reusser(a)actel.com> wrote in message news:5E916BAE1732F344BAFD713DF2373479016EA059@SV-MSG-01.amer.actel.com.. . I am using the serialization library in boost 1.33.1. I am compiling on windows using the VC 7.1 compiler. The problem I am having is that when I use xml_iarchive and xml_oarchive, everything works just fine for simple cases, but if the xml gets very deep ( same exact class hierarchy, just more data organized a little more complexly) I am getting runtime stack overflow crashes in the spirit parser. I figured I could solve that by simply substituting text_iarchive and text_oarchive. Please note that I am simply substituting in these archive types instead of using the xml archive headers, which work. There are no other code changes anywhere. Now I am getting the following compiler error: \boost\mpl\eval_if.hpp(40) : fatal error C1204: compiler limit : internal structure overflow Any suggestions? I can try increasing the stack size of my current application to eliminate the xml runtime stack overflow problem, but I am uneasy doing this until I understand how to calculate the stack sizes required, and why it is happening. Furthermore, I would prefer using the text archives, since the data is more compact than the xml ones. Ed Reusser Principal Software Engineer Actel Corporation (408) 318-4972 ________________________________ The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information. ________________________________ _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information.

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[Boost.Test} exit codes
by Christoph 13 Nov '06

13 Nov '06

Hi, I am experimenting with the Boost.Test framework. I have stumbled upon the exit code of the test program. I have not found the documentation on the exit code (maybe I have overlooked it) and am somewhat baffled how to interpret it: i) what is the semantic of the exit code? It seems to be 0 when all tests are passed (as expected), but I get 201 if some tests fail. What does 201 mean? Are there further possibilities? ii) is it possible have the exit code return the number of failed test cases? Thank you Christoph

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[enable_if][type_traits] Overload resolution question
by Michael Marcin 13 Nov '06

13 Nov '06

Hello, I have a fixed point math class and I want to enable some optimized operator overloads. for instance: fixed& fixed::operator /= ( const fixed &rhs ); fixed& fixed::operator /= ( int n ); it seems however to me that what I really want is an overload like: template< typename T > fixed& operator /= ( typename boost::enable_if<boost::is_integral<T>,T>::type n ); However I can't seem to get that function considered for overload resolution instead it goes through the following constructor and calls the /= that takes a const fixed &. template< typename T > fixed::fixed( T n, typename boost::enable_if< boost::is_integral<T> >::type* = 0 ); Speaking of which I don't understand why the following doesn't work in place of the previous constructor. template< typename T > fixed::fixed( typename boost::enable_if< boost::is_integral<T>,T>::type n ); Finally I'm using this class to replace a lot of hardcoded / macro logic and often as an optimization the code uses binary shifts to represent power of 2 multiply/divides. Going forward these divides need to work with both fixed and floating point types so f >> 1 needs to change to f / 2. Is it possible to create an overload for the / and * operators that determine if the operand is an integral constant and is a power of 2 and use a binary shift internally? Thanks, Michael Marcin

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Re: [Boost-users] [Serialization] unexpected assert registeringclasses
by Reusser, Edward 13 Nov '06

13 Nov '06

Robert, Thanks for the quick response. I have ensured that the serialization for each type is located in exactly one place. The header files where the serialization code resides for the derived classes are not global, that is, our build system is set up to ensure that no other library or DLL can reference them. I believe that I can make the serialization completely independent and contained inside the DLL without much difficulty. However, unless I statically link the serialization library, I don't think I can prevent the macro: BOOST_CLASS_EXPORT_GUID( class, "ClassNameText" ) from initializing the global table inside the serialization DLL (which is dynamically linked). I noticed that when I tried to use the other registration technique you describe, register_type<T>(), this also calls the registration code in the serialization DLL on load, so that doesn't solve the problem. It doesn't seem very practical to serializing in/out a prototype of each derived class into the archive initially because it would increase the archive size by a lot. Too bad there isn't a mechanism for creating a registration table specific to the DLL where the classes are serialized. If the global table was of the following structure: using namespace std; map< HMODULE, map<string, ETI*> >; Then the above macro would simply use AfxGetInstanceHandle (in the case of windows, I am unsure what the corresponding calls in other OS's would be), to pass the HMODULE handle. Ed -----Original Message----- From: Robert Ramey [mailto:ramey@rrsd.com] Sent: Monday, November 13, 2006 8:24 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [Serialization] unexpected assert registeringclasses Having serialization code in DLLS has raised some stick issues. The basic problem is the existence of a global table of information about types being serialized. Among other thngs, this global type table contains the export string name (GUID) that is shared among programs to identify the type. This table also points to functions via a virtual function mechnamism to implementations required by serialization. Entries are added to this table when code is loaded and deleted when code is unloaded. in version 1.33 I included the indicated assert - as it seemed to me that this must be unique. I was concerned that multiple entries in the table might point to different function implementations - as indeed they will. So I included this assertion. This started to create problems as you have found. Also I've now come to thnk that the having multiple entries for the same type is harmless - and difficult to avoid in the presence of dynamically loaded/unloaded DLLS. So in 1.34 - I commmented out the assertion. In addition, I've augmented the code to make sure that the correct entry in the table is deleted when the corresponding DLL is unloaded. So I believe that starting in 1.34 this problem will be resolved. I really don't know for sure because its very hard to come up with a good test for this. So, I think this problem is addressed. But in the face of dynamically loaded DLLs - which are not all guarenteed to be in sync ( some could have older versions of code), I think that the best policy would be to be sure that serialzation code for a particular type should be found in one and only one place. Also, doing this will result in smaller DLLS and applications. Doing this requires that one explicitly orgranize his code so to achieve this. This means avoiding instantiation of serialization code in applications and by explicitly instantiation such code in the DLLS. The closest guide I have for doing this is demo_pimpl which shows how to do this. Robert Ramey "Reusser, Edward" <Edward.Reusser(a)actel.com> wrote in message news:5E916BAE1732F344BAFD713DF2373479016EA054@SV-MSG-01.amer.actel.com.. . I am using the boost 1.33.1 distribution, and the xml_iarchive and xml_oachive to serialize a rather deep and complex data structure to xml. I am using make_nvp directly in all cases (not the macro). I am sometimes getting the following assert (line 71 in extended_type_info.cpp) when I load previously serialized data: assert( lookup(eti) == m_self->m_map.end() ); It seems obvious that what is happening is that somehow I am calling self_register more than once for a specific class. Tracing through the code however I am puzzled exactly how this could happen, since the registration should only happen once when the libraries are loaded. This never happens on save by the way, only on load. It also never happens if I do the save, followed by a load immediately. It only happens if I do the save, shut down the application, then load the data. I have verified that the loaded data is a bit by bit equivalent in both cases. The best that I can come up with is that I am loading the serialization library as a side effect of calling LoadLibrary at runtime. So I am linking in the serialization library after everything else has been loaded and is running. But again, none of the libraries are ever unloaded, and the load sequence should always be the same. The actual situation is that I have a library . call it Library A, which is linked to libraries B, and C. The library A is being linked using the LoadLibrary call, each of libraries B are C are linked to the boost serialization library. In each of libraries B, and C, I have used the macro: BOOST_CLASS_EXPORT_GUID( class, "ClassNameText" ) To define all of my classes I am serializing, including all classes that I am serializing using shared_ptr's. I was thinking originally that the problems were all shared_ptr's of classes that are derived from enable_shared_from_this<T>, but I am no longer confident that has anything to do with it. In fact, truth be told, I have no idea if any of the above has anything to do with the problem. When I commented out the assertion, everything seems to work just fine, except now I am getting a stack overflow on very complex hierarchies in the spirit parser (again, load only), but the simpler ones seem to work repeatedly without any problems. I have no doubt that the assertion was added there for a reason, so I hate to comment it out without finding out what else I might have broken. Edward Reusser Principal Engineer Actel Corporation (650) 318-4972 The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[Serialization] a coupla crashes from hiearchy complexity
by Reusser, Edward 13 Nov '06

13 Nov '06

I am using the serialization library in boost 1.33.1. I am compiling on windows using the VC 7.1 compiler. The problem I am having is that when I use xml_iarchive and xml_oarchive, everything works just fine for simple cases, but if the xml gets very deep ( same exact class hierarchy, just more data organized a little more complexly) I am getting runtime stack overflow crashes in the spirit parser. I figured I could solve that by simply substituting text_iarchive and text_oarchive. Please note that I am simply substituting in these archive types instead of using the xml archive headers, which work. There are no other code changes anywhere. Now I am getting the following compiler error: \boost\mpl\eval_if.hpp(40) : fatal error C1204: compiler limit : internal structure overflow Any suggestions? I can try increasing the stack size of my current application to eliminate the xml runtime stack overflow problem, but I am uneasy doing this until I understand how to calculate the stack sizes required, and why it is happening. Furthermore, I would prefer using the text archives, since the data is more compact than the xml ones. Ed Reusser Principal Software Engineer Actel Corporation (408) 318-4972 The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information.

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[Serialization] unexpected assert registering classes
by Reusser, Edward 13 Nov '06

13 Nov '06

I am using the boost 1.33.1 distribution, and the xml_iarchive and xml_oachive to serialize a rather deep and complex data structure to xml. I am using make_nvp directly in all cases (not the macro). I am sometimes getting the following assert (line 71 in extended_type_info.cpp) when I load previously serialized data: assert( lookup(eti) == m_self->m_map.end() ); It seems obvious that what is happening is that somehow I am calling self_register more than once for a specific class. Tracing through the code however I am puzzled exactly how this could happen, since the registration should only happen once when the libraries are loaded. This never happens on save by the way, only on load. It also never happens if I do the save, followed by a load immediately. It only happens if I do the save, shut down the application, then load the data. I have verified that the loaded data is a bit by bit equivalent in both cases. The best that I can come up with is that I am loading the serialization library as a side effect of calling LoadLibrary at runtime. So I am linking in the serialization library after everything else has been loaded and is running. But again, none of the libraries are ever unloaded, and the load sequence should always be the same. The actual situation is that I have a library ... call it Library A, which is linked to libraries B, and C. The library A is being linked using the LoadLibrary call, each of libraries B are C are linked to the boost serialization library. In each of libraries B, and C, I have used the macro: BOOST_CLASS_EXPORT_GUID( class, "ClassNameText" ) To define all of my classes I am serializing, including all classes that I am serializing using shared_ptr's. I was thinking originally that the problems were all shared_ptr's of classes that are derived from enable_shared_from_this<T>, but I am no longer confident that has anything to do with it. In fact, truth be told, I have no idea if any of the above has anything to do with the problem. When I commented out the assertion, everything seems to work just fine, except now I am getting a stack overflow on very complex hierarchies in the spirit parser (again, load only), but the simpler ones seem to work repeatedly without any problems. I have no doubt that the assertion was added there for a reason, so I hate to comment it out without finding out what else I might have broken... Edward Reusser Principal Engineer Actel Corporation (650) 318-4972 The information contained in or attached to this email may be subject to the Export Administration Regulations (EAR), administered by the U.S. Department of Commerce, or the International Traffic in Arms Regulations (ITAR), administered by the U.S. Department of State, and may require an export license from the Commerce or State Department prior to its export. An export can include a release or disclosure to a foreign national inside or outside the United States. Include this notice with any reproduced portion of this information.

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Iterater for subset extraction?
by Thom DeCarlo 12 Nov '06

12 Nov '06

I have a couple of n00b questions. I have constructed a BGL graph that uses the edge_name_t property to road names. I want to change the weights of some of the roads based on input from the user. Is there a way to set up an iterator to step through edges that have names which match elements of a set? (e.g., "A,B,B1,L,M") In a related question, I need to extract a vertex whose vertex_index_t value matches a specific value. The vertices were not entered in any specific order, so the "vertex(1, g)" function returns the first vertex to have been entered into the graph, but not necessarily the one whose index value is "1". Thanks, Thom -- this sig intentionally left blank

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format un-debuggability
by Drumheller, Michael 12 Nov '06

12 Nov '06

If you don't pass enough arguments to a boost::format you get this: "boost::too_few_args: format-string refered to more arguments than were passed" Unfortunately there is, as far as I can tell, no way to figure out where the error happened, other than building a debug version of your app and breaking into the debugger on that error. Needless to say that can be very inconvenient. Would it be possible to fix boost::format (which, by the way, is IMHO one of the most wonderful of all the Boost libraries!!) so that its exceptions carry a little more information about their origins (e.g., embedding the format-string itself in the message)? Thank you. Michael Drumheller Boeing Phantom Works Mathematics and Engineering Analysis 425.373.2703 michael.drumheller(a)boeing.com This email may contain proprietary information. If you are not the intended recipient please delete it and notify the sender that you received it in error.

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Boost crosscompilation
by Vinh 12 Nov '06

12 Nov '06

Hi everyone, I'm new to boost and have successfully installed it on my debian sarge system. For a particle Filter using the Bayes++ Library, I would need to crosscompile the boost library for an ARM processor. Does anyone know whether that is possible? (I already have a crosscompiler installed, but don't know whether boost supports crosscompilation?) Vinh

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iterating over arbitrary python object in c++
by Augusto Callejas 12 Nov '06

12 Nov '06

hi- i'm writing a C++ class that i want to expose as a python class. one method in my class has an argument that takes in a python object that "implements" the iterator interface (that is the python object has defined "__iter__" and "__next__" and can be used in a "for x in y" loop). how do i go about iterating over that python object in my C++ code? for example: void my_class::method(object my_iterable_obj) { // iterate over "my_iterable_obj" } one method i tried was calling the "__next__" method explicity: my_iterable_obj.attr("__next__")() however, "__next__" raises a StopIteration exception when there are no more objects in the iterator. i could not find any examples in the boost python tutorials for handling python exceptions from c++. is there another way i can go about this? thanks, augusto.

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[Boost.Signals] in Multithreaded Environment
by Terry G 11 Nov '06

11 Nov '06

Hello again everyone! Boo ST == (Scarey signals & threads) Signals/slots are just too good not to use in a multi-threaded environment. Someday, this will be fixed, I know. But for now... I'm trying to serialize access to boost.signals using Bjarne Stroustrups "wrapper" concept. Here's what I'm doing. Is this likely to cause problems? Sorry about the length. If this is too dangerous, what's a better alternative? I typed this from memory and didn't try to compile. Please disregard any typos or syntactic blunders. // Implements Bjarne Stroustrup's "wrapper" concept using boost::shared_ptr. template <typename T> class Wrapper { T* p; public: explicit Wrapper(T& obj) : p(&obj) { } boost::shared_ptr<T> get() const { p->prefix(); return boost::shared_ptr<T>(p, boost::mem_fn(&T::suffix)); } // get boost::shared_ptr<T> operator->() const { return get(); } }; //Wrapper // Provides signals through "safe" wrapper. (?) class TiePoint { public: class Events { Mutex lock; // Provided elsewhere. void prefix() { lock.acquire(); } void suffix() { lock.release(); } friend class Wrapper<Events>; public: boost::signal<void (Signal1Args)> signal1; boost::signal<void (Signal2Args)> signal2; // etc... template <class Iter> void disconnect(Iter begin_, Iter end_) { std::for_each(begin_, end_, boost::mem_fn(&boost::signals::connection::disconnect); } // disconnect }; // Events private: Events _events; public: Wrapper<Events> events; TiePoint() : _events(), event(_events) { } }; // TiePoint // Demonstrates use of TiePoint class. class UsesSignals { private: void handle1(Signal1Args) { ... } void handle2(Signal2Args) { ... } std::vector<boost::signals::connection> conns; // Be very careful with these. public: void connect(TiePoint& tiePt) { boost::shared_ptr<TiePoint::Events> events = tiePt.events.get(); conns.push_back(events->signal1.connect(Handle1)); conns.push_back(events->signal2.connect(Handle2)); } // connect void disconnect(TiePoint& tiePt) { tiePt.events->disconnect(conns.begin(), conns.end()); conns.clear(); } // disconnect void signalJustOne(TiePoint& tiePt) { tiePt.events->signal1(signal1args); } // signalJustOne void signalMany(TiePt& tiePt) { boost::shared_ptr<MyClass::Events> events = tiePt.events.get(); events->signal1(signal1args); events->signal2(signal2args); ... } // signalMany }; // UsesSignals

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Serialization of an std::list into XML without a NVP
by Devin Fallak 10 Nov '06

10 Nov '06

Hi all, I'm working with the Serialization library and trying to output a list of objects into an XML file. The problem I'm having is that in serializing a std::list, the Serialization library requires that the list itself is given a NVP. The specification I'm working with requires a list of undefined length WITHOUT its own NVP. Is there any way to serialize a std::list into/out of an xml_oarchive/xml_iarchive? Any help would be much appreciated. Thanks, Devin Fallak

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Problem with counting iterator and bind
by Maitre Bart 10 Nov '06

10 Nov '06

I have this: typedef LegacySequentialContainer<string> LegacyStringVector; LegacyStringVector lsv; // ... filling lsv with strings ... I realized this: boost::counting_iterator<int> it(0); boost::counting_iterator<int> end(lsv.length()); while (it < end) cout << boost::bind(&LegacyStringVector::operator[], v3, _1)(*it++) << " "; cout << "\n"; and it works. However, I wish to do the same but using std::copy or std::for_each instead. I tried the following but none is able to compile: copy(boost::counting_iterator<int>(0), boost::counting_iterator<int>(v3.size()), boost::bind(ostream_iterator<string>(cout, " "), &vector<string>::operator[], v3, _1)); copy(boost::counting_iterator<int>(0), boost::counting_iterator<int>(v3.size()), boost::bind(ostream_iterator<string>(cout, " "), boost::bind<string,int>(&vector<string>::operator[], v3, _1))); copy(boost::counting_iterator<int>(0), boost::counting_iterator<int>(v3.size()), boost::bind(ostream_iterator<string>(cout, " "), boost::bind<string,int>(&vector<string>::operator[], v3), _1)); I must be close to the solution but error messages do not help guiding me in the right direction. Anyone has any suggestion?

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reference to void in shared_ptr_nmt
by Oliver Kania 10 Nov '06

10 Nov '06

Hello, I am encountering the following problem when using boost with shared pointers (Ubuntu Edgy, G++4.1/4.0/3.4): ======================= /usr/include/boost/detail/shared_ptr_nmt.hpp:115: error: forming reference to void shared_ptr_nmt.hpp:114: error: forming reference to void ========================== the source code reads : ========================= T & operator*() const // never throws { BOOST_ASSERT(px != 0); return *px; } ========================= To me, this seems like a g++ (GNU GCC) problem, (It seems that G++ checks if void would be a viable substitutiion for T) however, I have tried three different versions of g++ and get the same result every time. There once was such a bug in GCC but it has been resolved ages ago. Regards, Oliver Kania

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Building Boost on Solaris 10/Sparc: No release version of libraries?
by Boris 10 Nov '06

10 Nov '06

I built Boost 1.33.1 on a Solaris 10/Sparc machine. Problem is that no release version of the various libraries are built. There is for example libboost_date_time-gcc-d-1_33_1.so but no libboost_date_time-gcc-mt-s-1_33_1.so. Is this a known problem on Solaris? The Solaris machine has GCC 3.4.6 installed. I built bjam myself (with tools/build/jam_src/buid.sh) and then entered: ./bjam "-sTOOLS=gcc" "-sBUILD=<define>NO_BZIP2" --without-python stage When I look then into stage/lib there are only debug versions of the libraries? Boris

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[WAVE] position of tokens
by Andreas Sæbjørnsen 10 Nov '06

10 Nov '06

Hi, I need some advice regarding Wave. What I want to do is to operate with Wave on a token stream and extract the token stream representing macro calls after expansion. The twist is that I want the token stream after expansion to have the positions that another preprocessor would see on the already expanded output from Wave. E.g: #define MACRO_CALL int x; int main(){ MACRO }; Exands into #line 2 int main(){ int x; }; Where 'int x' should have a position of line 3 instead of line 1 after expansion. I also want the column number to represent what we see on line 3 instead of what we see on line 1. Is this possible ? Thanks Andreas

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