C / C++ / MFC

Aescleal wrote:

The reason for that is that the compiler can't assume that i is fixed any more (you've told it that something somewhere could modify it) so there's a real variable behind it.

Aescleal wrote:

You're still not allowed to modify it through i though! This sort of trick is really handy for overlaying C++ objects on ranges of addresses for memory mapped devices.

Code-o-mat wrote:

I think you shouldn't be able to do it, since usually things are declared as const for a reason

Aescleal wrote:

Responsible adult? You've never worked in the games industry Biggest bunch of hackers (in the bad sense) out there.

cout << "j= " << j << endl;
0041143A  mov         eax,dword ptr [__imp_std::endl (4182B4h)]
0041143F  push        eax
00411440  mov         ecx,dword ptr [j] <=============== MEMORY ADDRESS
00411443  mov         edx,dword ptr [ecx]
00411445  push        edx
00411446  push        offset string "j= " (41570Ch)
0041144B  mov         eax,dword ptr [__imp_std::cout (4182BCh)]
00411450  push        eax
00411451  call        std::operator<<<std::char_traits<char> > (4110F0h)
00411456  add         esp,8
00411459  mov         ecx,eax
0041145B  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (4182C0h)]
00411461  mov         ecx,eax
00411463  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (4182C4h)]

cout << "i= " << i << endl;
00411469  mov         eax,dword ptr [__imp_std::endl (4182B4h)]
0041146E  push        eax
0041146F  push        0Ah  <================= LITERAL (10)
00411471  push        offset string "i= " (415710h)
00411476  mov         ecx,dword ptr [__imp_std::cout (4182BCh)]
0041147C  push        ecx
0041147D  call        std::operator<<<std::char_traits<char> > (4110F0h)
00411482  add         esp,8
00411485  mov         ecx,eax
00411487  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (4182C0h)]
0041148D  mov         ecx,eax
0041148F  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (4182C4h)]

const int& j = i; // do not cast away const-ness

Aabid wrote:

the previous behavior and that is still a mystery!

const int i = 10;
int& j = (int&)i;

const int i = 10;

int x = 10;

cout << "i= " << 10 << endl;
cout << "j= " << x << endl;
cout << "&i= " << &x << endl;
cout << "&j= " << &x << endl;

x++;

cout << "j= " << x << endl;
cout << "i= " << 10 << endl;

Aabid wrote:

the code declares a const integer and a reference to it. incrementing a reference adds 1 to j and outputs as 11, that is fine.

wangafei wrote:

but it's best to use mfc

Rajeev.Goutham wrote:

Problem is existing application in non mfc. for displaying a small dialog do i need to make that existing application also Mfc one. please guide.