fork download
copy 
  1. #include <iostream>
  2. #include <cstdio>
  3.  
  4. using namespace std;
  5.  
  6. struct A
  7. {
  8.     virtual void func()
  9.     {
  10.       printf("i: %d\n", i_);
  11.     }
  12.     void inc()
  13.     {
  14.       ++i_;
  15.     }
  16.     A()
  17.     {
  18.       i_=10;
  19.     }
  20.     private:
  21.       int i_;
  22. };
  23.  
  24.  
  25. int main()
  26. {
  27.   void (A::*p)() = &A::func;
  28.  
  29.   A a;
  30.   (a.*p)();
  31.  
  32.   unsigned int vptr_addr = *(unsigned int *)&a;
  33.   cout << "vptr_addr:" << hex << vptr_addr << endl;
  34.  
  35.   unsigned int func_addr = *(unsigned int *)vptr_addr;
  36.   cout << "func_addr:" << hex << func_addr << endl;
  37.   a.inc();
  38.   (*(void(*)(A*))(func_addr) )(&a);
  39.  
  40.   A aa;
  41.   (*(void(*)(A*))(func_addr) )(&aa);
  42.  
  43.   (*(void(*)(A*))(func_addr) )(&a);
  44.  
  45.   (*(void(*)(A*))(func_addr) )(&aa);
  46.  
  47.   return 0;
  48. }  
  49.  
Success #stdin #stdout 0s 3340KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
i: 10
vptr_addr:8048958
func_addr:8048870
i: 11
i: 10
i: 11
i: 10
https://ideone.com/KLP0gG
language:
C++ (gcc 8.3)
created:
11 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!