Not sure what you mean by class memory. Are you trying to distinguish between class vs instances? If so, yes, I believe the vtable should be per class, since the this pointer is probably the first one to be pushed in non-static members call, it wouldnt make sense to have a separated copy for each instance. I may be wrong here, though...
On Mon, Mar 28, 2011 at 1:31 PM, Amit Basak <[email protected]> wrote: > Theoretically, the vtable conatins pointer to each virtual function of the > class. > Each object of this class contains a pointer called vptr to this virtual > table. > But will the space occupied by the v-table be part of the memory occupied by > the class? > If the memory needed by v-table is part of class, then the class memory size > will be increased by 4n, where n is the number of virtual functions in the > class and the machine is 32 bit. > Please correct me if I am wrong. > Would appreciate if someone clarifies if the vtable is created in class > memory or in any other memory space. > -- > Thanks, > Amit Kumar Basak > > On Tue, Mar 29, 2011 at 1:47 AM, hammett <[email protected]> wrote: >> >> Off the top of my head, virtual functions are implemented through >> v-tables http://en.wikipedia.org/wiki/Virtual_table >> The size should be the size of a native pointer (4 bytes in 32 >> machines) but I could be wrong. >> >> >> On Mon, Mar 28, 2011 at 11:37 AM, himanshu kansal >> <[email protected]> wrote: >> > can u gv any link for reference...??? >> > >> > On Sat, Mar 26, 2011 at 12:29 PM, D.N.Vishwakarma@IITR >> > <[email protected]> >> > wrote: >> >> >> >> there is vtable known as virtual table which contains addresses of >> >> virtual >> >> functions . >> >> And there is vptr a pointer that points to vtable of that class space >> >> occupied by class having virtual function wil be equal to space >> >> occupied by >> >> a pointer * number of virtual functions .. >> >> I think this if there is any correction please let me know... >> >> >> >> On Sat, Mar 26, 2011 at 12:00 PM, himanshu kansal >> >> <[email protected]> wrote: >> >>> >> >>> wht is the space occupied by a class in c++ whn it contains a virtual >> >>> fn..... >> >>> How are the virtual fn implemented internally by c++....... >> >>> >> >>> -- >> >>> You received this message because you are subscribed to the Google >> >>> Groups >> >>> "Algorithm Geeks" group. >> >>> To post to this group, send email to [email protected]. >> >>> To unsubscribe from this group, send email to >> >>> [email protected]. >> >>> For more options, visit this group at >> >>> http://groups.google.com/group/algogeeks?hl=en. >> >>> >> >> >> >> >> >> >> >> -- >> >> With Regards >> >> Deoki Nandan Vishwakarma >> >> IITR MCA >> >> Mathematics Department >> >> >> >> -- >> >> You received this message because you are subscribed to the Google >> >> Groups >> >> "Algorithm Geeks" group. >> >> To post to this group, send email to [email protected]. >> >> To unsubscribe from this group, send email to >> >> [email protected]. >> >> For more options, visit this group at >> >> http://groups.google.com/group/algogeeks?hl=en. >> > >> > -- >> > You received this message because you are subscribed to the Google >> > Groups >> > "Algorithm Geeks" group. >> > To post to this group, send email to [email protected]. >> > To unsubscribe from this group, send email to >> > [email protected]. >> > For more options, visit this group at >> > http://groups.google.com/group/algogeeks?hl=en. >> > >> >> >> >> -- >> Cheers, >> hammett >> http://hammett.castleproject.org/ >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Algorithm Geeks" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/algogeeks?hl=en. >> > > > > > > -- Cheers, hammett http://hammett.castleproject.org/ -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
