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COM Memory Layout, Vtable, and Function Pointer Issues And Questions 15 Years Ago by Frederick2 …[/url] Where Asadullah Ansari methodically disects classes and vtables to call virtual functions just with C addresses and… Vtable [/CODE] Since we’ve located the respective Vtables in memory it should be thoretically possible to call… of a class being pointers to one or multiple VTABLES – is that a standardized C++ construction or just… Re: COM Memory Layout, Vtable, and Function Pointer Issues And Questions 15 Years Ago by Frederick2 …n"); for(i=0;i<2;i++) //Two VTABLES! Iterate Through Them. The 1st VTABLE Pointer Occupies Bytes {… calling the five functions contained in each interface. { //The VTABLEs contain pointers to the respective interface functions. printf ( "… Re: COM Memory Layout, Vtable, and Function Pointer Issues And Questions 15 Years Ago by ArkM … I have never seen top secret manuals about COM or vtables). It seems you try to discover terra incognita where COM…==C++ class object layout. But this triad: COM, C++ and vtables live in different namespaces... Yes, MS used the same Windows… vtable 18 Years Ago by durga prasad d Hi all, What is vtable ? How many vtables created for this sample. class A { virtual void myFunc() = 0; }; … Re: vtable 18 Years Ago by Narue >What is vtable ? A fancy term for an array of function pointers. >How many vtables created for this sample. Maybe none. The virtual mechanism doesn't [b]have[/b] to be implemented using the vtable concept. However, if it did, the answer would probably be one, but it's implementation-defined. Create Virtual __stdcall Function That Wonâ€™t Crash When Called Using A Fn Ptr 15 Years Ago by Frederick2 … for each Vtable) the addresses of the functions in the Vtables and calls those functions through a suitably cast function pointer… new, malloc and a class 11 Years Ago by TheBusDriver … empty (?). I'm guessing it has something to do with vtables but I'm not sure how to fix it (if… Re: new, malloc and a class 11 Years Ago by mike_2000_17 …). > I'm guessing it has something to do with vtables but I'm not sure how to fix it (if… Re: new, malloc and a class 11 Years Ago by TheBusDriver That's a bummer. I think the way `new` works is horrible but there's nothing I can do short of implementing my own vtables with function pointers. Thanks anyway. [Linker error] undefined referance to... vtables and static members 10 Years Ago by Tsaou I keep getting loads of linker errors that probably have something to do with virtual-functions/definitions and/or static class members... I've seen several relevant posts but none of the solutions suggested work, can you see wht the problem is here? My projects consists of 3 files: BALLS.H #include <iostream> using namespace… Re: [Linker error] undefined referance to... vtables and static members 10 Years Ago by Ancient Dragon You have static data in some of the classes that also need to be declared globally in one of the \*cpp files. Static class data is just like normal global data except they contain the class scope operator. For example you might declare them in main.cpp like this example #include <iostream> #include <cstdlib> #include <… Re: [Linker error] undefined referance to... vtables and static members 10 Years Ago by Tsaou Thanks a lot it works now... What i can't understand though is that since the "#include 'Balls'" commands the preprocessor(before calling the compiler or the linker!) to replace it with the .h file contents, the static field are therefore declared in the cpp file... Why doing it again fixes the problem(and doesn't create others like … Re: [Linker error] undefined referance to... vtables and static members 10 Years Ago by Ancient Dragon Because c++ standards stay that's the way it has to be done. Just declaring an object static in the class declaration isn't enough -- the static objects also have to be declared just like ordinary global data; that's actually what they are. Re: VTABLE 14 Years Ago by Frederick2 …] However, there are a couple of books that describe how vtables typically work internally, given the full understanding that exact details… discussion I wrote a few tutorials on my explorations of VTABLES and COM memory layout, and they can be found here… Re: Implementing Vtable in C 14 Years Ago by Tom Gunn Here is a simple example of one way to implement vtables in C: [code] #include <stdio.h> /* class definitions */ … the end result is the effect of late binding. Even vtables are not required, but it is a common implementation in… Re: How Virtual does work?? 13 Years Ago by Narue … from compiler to compiler, but a typical implementation will generate vtables at build time. So when your program is loaded into… memory, the vtables are already set up for the inheritance hierarchy. The constructor… Re: need some help with sizeof(class) 17 Years Ago by jwenting [QUOTE=sunnypalsingh;291333]But class B doesn't have any virtual function? So what's the point of pointer to virtual table for class B? Isn't the sizeof class B 4 because of the subobject A?[/QUOTE] Narue was speaking in general terms. VTables do influence class size, just as do data members of superclasses. Re: need some help with sizeof(class) 17 Years Ago by SpS [QUOTE=jwenting;291384]Narue was speaking in general terms. VTables do influence class size, just as do data members of superclasses.[/QUOTE] Actually she was quoting something else so I was thinking that. I don't doubt about her knowledge. Re: Undefined reference to 'vtable for ...' 16 Years Ago by vijayan121 … faq about this: [url]http://gcc.gnu.org/faq.html#vtables[/url] > Am I to assume that the example in… Re: Multiple Inheritance: Ambiguous Function 15 Years Ago by Clockowl … compiler creates only one car inside of racetank, and 2 vtables to be able to still call the functions. Basically, I… Re: Multiple Inheritance: Ambiguous Function 15 Years Ago by NicAx64 … compiler creates only one car inside of racetank, and 2 vtables to be able to still call the functions.[/QUOTE] and… Re: VTABLE 14 Years Ago by Narue …&sr=1-1"]books[/URL] that describe how vtables typically work internally, given the full understanding that exact details… Re: How to access VPTR in my program? 14 Years Ago by Frederick2 … pretty much take COM memory apart and look close at VTables, VTable pointers, function pointers, calling class member functions using function… Re: Virtual table 13 Years Ago by Frederick2 Lot of info here too. I prefer base pointer notation in working with VPTRs ant VTables... [url]http://www.jose.it-berater.org/smfforum/index.php?topic=2980.0[/url] Re: Detail about How VPTR and Virtual table works 12 Years Ago by Nihalani There will be four VTables i guess,three for the base classes and one for the derived class which will have the entries for all the virtual function addresses of the base classes it is derived from and its own virtual function addresses. Re: Ubuntu 11.10 64bit make advice 11 Years Ago by rubberman … is a bit weird since the errors are for missing vtables, and those are generated by the compiler for classes with… Re: Researching C++ - Your Opinions Wanted Here! 11 Years Ago by L7Sqr … for you and leads to a more painful debugging experience. Vtables, inheretance, templates all complicate the process of reading and understanding… Re: COM Memory Layout, Vtable, and Function Pointer Issues And Questions 15 Years Ago by Alex Edwards ...If you haven't already, I strongly suggest that you read Inside The C++ Object Model (by Stanley B. Lippman). Re: Create Virtual __stdcall Function That Wonâ€™t Crash When Called Using A Fn Ptr 15 Years Ago by Frederick2 Well, nobody seems to be replying to my thread in terms of telling me what my error is, and I took that as being ignored. However, in the meantime I just tried a neat piece of code posted several weeks ago by vijayan121 at... [url]http://www.daniweb.com/forums/thread141366.html[/url] and that crashes too after providing correct output - just … Re: Create Virtual __stdcall Function That Wonâ€™t Crash When Called Using A Fn Ptr 15 Years Ago by dougy83 I tried your program, seemed to run in dev-c++ & visual-c++2008 (with the reported error). Tried debugging it, saw that the stack pointer certainly is different before call to after call (that's bad) - it's due to the function doing a ret 4, when it should be a ret 0... any idea what it's popping?? (i reckon it's 'this') Have a look at: […