- Boost-users - lists.boost.org

Re: [Boost-Users] MS VS 6: passing boost::shared_ptr<T> to a dll function
by Peter Dimov 18 Jun '02

18 Jun '02

Your problem was that the EXE was using the single-threaded runtime, but the DLL has been set to multithreaded. The mutex lock in the DLL was spinning forever. When I set both to multi-threaded, it works, even with different heaps. Interesting issue. It can be made to work even in this case but this will cost performance. ----- Original Message ----- From: <corno(a)dds.nl> To: "Peter Dimov" <pdimov(a)mmltd.net> Sent: Tuesday, June 18, 2002 13:52 Subject: Re: [Boost-Users] MS VS 6: passing boost::shared_ptr<T> to a dll function > hmmmm.... > 2nd try :) > > > Did you forget the attachment? ;-) > > > > ----- Original Message ----- > > From: <corno(a)dds.nl> > > To: <pdimov(a)mmltd.net> > > Sent: Tuesday, June 18, 2002 0:39 > > Subject: Re: [Boost-Users] MS VS 6: passing boost::shared_ptr<T> to a dll > > function > > > > > > > > > > > > Thanx Craig, that turned out to be the problem for VC++ as well. > > > > > > > > Yep, but shared_ptr is supposed to work in this case, in theory. ;-) > > I'll > > > > look into this. Any more information that can help me find the problem? > > > > > > > > > > Peter, > > > > > > I made 2 small projects that illustrate the problem. (change the path to > > the > > > boost lib ofcourse) > > > It can very likely be that I am doing something terribly stupid :) but > > anyways, > > > here's what I see; > > > > > > If I build and run it with a single memory manager I see output for all 4 > > steps. > > > If I build and run it with separated memory managers I see output for > > step > > 1 > > > and 2 only and then it hangs. > > > > > > Corno > > > > > > > > > > >

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boost::threads queation
by Peter 18 Jun '02

18 Jun '02

Is it possible to pass a pointer of a class member function into a thread ?? I have no problems passing functions (or pointers to functions rather) which are not members of any classes. However when I try to pass member functions, I get compile errors. I am using MSVS 6.0 on win 2000. The following is a simplified model of my situation. I am trying to create a thread inside a function of one class and pass into it, a pointer of a member function of another class: // all necessary includes; class testClass1 { public: // constructor testClass1() { // init code} ~testClass1() {} void fun1() { // some code} }; class testClass2 { testClass2() { // init code} ~testClass2() {} // SEE HERE PLEASE void fun2() { // some code.. boost::thread myThread(&object1.fun1) ; // PROBLEM HERE // more code... } testClass1 object1; }; int main(int argc, char **argv) { testClass2 class2; // some code... class2.fun2(); // more code.... return 0; } Any help would be greatly appreciated. Thanks in advance. Peter

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new to boost::threads - question
by Peter 18 Jun '02

18 Jun '02

Is it possible to pass a pointer of a class member function into a thread ?? I have no problems passing functions (or pointers to functions rather) which are not members of any classes. However when I try to pass member functions, I get compile errors. I am using MSVS 6.0 on win 2000. The following is a simplified model of my situation. I am trying to create a thread inside a function of one class and pass into it, a pointer of a member function of another class: // all necessary includes; class testClass1 { public: // constructor testClass1() { // init code} ~testClass1() {} void fun1() { // some code} }; class testClass2 { testClass2() { // init code} ~testClass2() {} // SEE HERE PLEASE void fun2() { // some code.. boost::thread myThread(&object1.fun1) ; // PROBLEM HERE // more code... } testClass1 object1; }; int main(int argc, char **argv) { testClass2 class2; // some code... class2.fun2(); // more code.... return 0; } Any help would be greatly appreciated. Thanks in advance. Peter

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RE: [Boost-Users] tolower not in std::
by bjorn.karlsson＠readsoft.com 17 Jun '02

17 Jun '02

> From: ccullum [mailto:yg-boost-users@m.gmane.org] > I am getting a message stating that tolower is not found in > the std::, but > transform can be found. Has anyone seen this before? > In future posts, please state the Boost library that is causing trouble. There is already one reply to this seemingly-close-to-being-off-topic note; another possibility is that you've simply failed to #include the header where tolower resides, which is <cctype>. Bjorn [Non-text portions of this message have been removed]

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tolower not in std::
by ccullum 17 Jun '02

17 Jun '02

I am getting a message stating that tolower is not found in the std::, but transform can be found. Has anyone seen this before? Thanks, Christopher cullum ccullum(a)uprizer.com

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[BGL] using Borland C++Builder 5
by Alex Henderson 17 Jun '02

17 Jun '02

Hi, I had a problem compiling both the test file (libs/graph/test/graph.cpp) and the first example (libs/graph/example/file_dependencies.cpp) of the BGL and traced the problem to the support for tuples. The offending line is line 40 of boost/tuple/tuple.hpp which incorporates tuples::get into the boost namespace. Commenting out this line allows the files above to compile and run OK. Leaving it in invokes an internal compiler error. The test file for tuples works OK with Builder 5 and so I guess there's a dependency somewhere. The question is - if I comment out this line am I going to get hit with problems elsewhere in the BGL? I'm new to the BGL and don't know whether the whole thing is built on the abilities of tuples. [Using boost_1_28_0, BCC5 sp1, Win2000 sp2] Thanks for any thoughts. Alex

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RE: [Boost-Users] MS VS 6: passing boost::shared_ptr<T> to a dll function
by Smith, Eric V. 16 Jun '02

16 Jun '02

How about some sample code? It's hard to help if we don't know exactly what you're trying to do. > -----Original Message----- > From: lognez [mailto:corno@dds.nl] > I am trying to pass a smart pointer (boost::shared_ptr<T>) as an > argument to > a function that is implemented by a dll and called by an executable, > but > whenever I execute the application, it goes into a loop, no matter > what the > type of T is. When the function is implemented in the exe or > when the function is called from inside the dll it works > fine. Does anybody have a clue what could be happening? BTW, > I'm not implicating a bug in boost, I know that it could as well > be a > MS VC++ bug but I would just like to know how this comes and how I > can solve > it.

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Re: Static power() function, to add in common_factor
by Daryle Walker 14 Jun '02

14 Jun '02

on 6/12/02 12:11 AM, ravioli(a)softhome.net wrote: > Is there an interest into having a power() template calculating the N-th power > of any number, when N is known at compile-time ?t uses the algorithm of the > STL power function(), and runs between two or three times faster, and maybe > could be of interest in the " <boost/math/common_factor.hpp> which provides > run-time and compile-time evaluation of the greatest common divisor (GCD) or > least common multiple (LCM) Proposals for new libraries usually go to the regular Boost list, not this one. Besides that: What would this have to do with the common-factor library? I've never heard of a function called "power". Is it a STL function that didn't get into the standard? Are there any docs for it? How do you know what algorithm it uses? > It simply works this way, for example to have PI at exponent three : > double a = power_const<3>( 3.14159) > > As the single include file is very short, please apologize if I give it > straight on, just to save your time and to have an idea how badly you judge my > poor code ;) [TRUNCATE code] I don't think your implementation will work for negative exponents. -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT mac DOT com

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Dynamic Bitset formal review - half way point
by Mat Marcus 14 Jun '02

14 Jun '02

Reminder - We have just past the half way point for the formal review of dynamic bitset. So far we have: 1 formal yes vote 1 formal no vote Discussion regarding iterators for dynamic bitset and comparison to vector<bool>. Some minor corrections and updates. I would like to see more formal reviews (including a yes or no vote) before the review period ends on the 17th. Thanks, Mat ##### > The formal review of Dynamic Bitset by Chuck Alison and > Jeremy Siek will commence today Saturday June 8th and run > through Monday, June 17th. > > The library is currently available at > <http://groups.yahoo.com/group/boost/files/dyn_bitset.tar.gz> > > > Below is an excerpt from the library's documentation: > > The dyn_bitset class represents a set of bits. It provides > accesses to the value of individual bits via an operator[] > and provides all of the bitwise operators that one can > apply to builtin integers, such as operator&& and > operator<<. The number of bits in the set is specified at > runtime via a parameter to the constructor of the > dyn_bitset. > > Each bit represents either the Boolean value true (set) or > false (reset). To toggle a bit is to change the value to > true if it is false and to false if it is true. Each bit > has a non-negative position pos. The position pos == 0 > corresponds to the least significant bit and pos == size() > - 1 is the most significant bit. When converting an > instance of dyn_bitset to or from an unsigned long, the > bit position pos corresponds to the bit value 1 << pos. > > The dyn_bitset class is nearly identical to the > std::bitset class. The difference is that the size of the > dyn_bitset (the number of bits) is specified at run-time > during the construction of a dyn_bitset object, whereas > the size of a std::bitset is specified at compile-time > through an integer template parameter. > > > For information about submitting a Formal Review, see > http://www.boost.org/more/formal_review_process.htm > > Please try out the library and comment during the review > period. Be sure to say whether or not you think the library > should be accepted by Boost. > > Compiler notes: This library has been tested using the > following compiler platforms: > > Gcc 2.95 and 3.01 > Kai C++ > Metrowerks Codewarrior 8 (beta, Mac) > Visual C++ 7.0 > Comeau > > The library presently requires template friend support and is > known not to compile with CodeWarrior 7.2 or Visual C++ 6.0. > > The library has not been tested with Borland. > > > The Formal Review manager is Mat Marcus. > > > > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost-announce

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RE: [Boost-Users] shared_ptr in Borland C++ Builder
by scleary＠jerviswebb.com 12 Jun '02

12 Jun '02

> From: Craigus [mailto:yg-boost-users@m.gmane.org] > > Hi > > I'm new to using the Boost library. Welcome! :) > I have Codeguard turned on (detects memory leaks, accessing freed memory, > overwriting memory illegally and the like). When the shared_ptr object > count goes to zero operator() in checked_deleter eventually gets called. > Codeguard is reporting (in poor English): > > Method called on illegally casted object If you want to fix the problem: uncheck Project Options -> C++ -> Zero length empty class members. Then rebuild (not remake). The rest of this e-mail is just explaining what the error is and why this fixes it. Here's the problem: CodeGuard is complaining that the 'this' pointer for the checked_deleter object is invalid when its operator() is called. (The error is not reported if you uncheck the "Validate the 'this' pointer on member function entry" and rebuild). Many function objects contain no data or base classes, but operator() cannot be static, so for these function objects (including checked_deleter), a sort of unspoken convention has arisen: never use the 'this' pointer. But CodeGuard validates the 'this' pointer anyway... In common implementations of Standard C++, CG's validation would work: in the case where a function object is used as a most-derived class, it has non-zero size (according to the Standard), so 'this' would reference a "placeholder" memory location for that object. in the case where a function object is used as a base class, then the most-derived class has non-zero size, and 'this' would reference a member in some derived class. C++ Builder, however, has a non-Standard-conforming option that is on by default: Project Options -> C++ -> Zero length empty class members. This creates a "loophole" in the first case described above: in the case where a function object is used as a most-derived class *as a member of another class*, it has zero-size(!) -- and therefore if it is the last member of that class, 'this' would reference memory *after* the most-derived class. Unchecking this option allows CG's validations to work in the way described above, closing the "loophole". Happy coding! :) -Steve

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