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This simple code

typedef strt B{
int b;
}BS;

typedef struct A:B
{
int a;
int foo(){return a+b;}
}AS;

int main()
{
AS*pab=new AS();
pab->b=4;
pab->a=5;
pab->a=pab->foo();

***********//Output result is incorrect only 4 //***********

delete pab;
}

Why isn't the output 9 as it is supposed to be ?

Thanks

On Jan 19, 3:46 pm, "Peter Liu" <ppp1234567890123456...@yahoo.co.id>
wrote:
> This simple code
>
> typedef strt B{
> int b;
>
> }BS;typedef struct A:B
> {
> int a;
> int foo(){return a+b;}
>
> }AS;int main()
> {
> AS*pab=new AS();
> pab->b=4;
> pab->a=5;
> pab->a=pab->foo();
>
> ***********//Output result is incorrect only 4 //***********
>
> delete pab;
>
> }Why isn't the output 9 as it is supposed to be ?

By converting it to C++ it works much better:

#include <iostream>

struct B{
int b;
};

struct A : public B
{
int a;
int foo(){return a+b;}

};

int main()
{
A* pab = new A();
pab->b=4;
pab->a=5;
std::cout << pab->foo();

delete pab;
}

Peter Liu wrote:

> This simple code
>
> typedef strt B{
? strt

> int foo(){return a+b;}
It works ok
movl 8(%ebp), %eax
movl 4(%eax), %edx //b->%edx
movl 8(%ebp), %eax
movl (%eax), %eax //a->%eax
leal (%edx,%eax), %eax // a+b->%eax !!! look like add !!!

Peter Liu wrote:
> This simple code
>
> typedef strt B{
> int b;
> }BS;
>
> typedef struct A:B
> {
> int a;
> int foo(){return a+b;}
> }AS;
>
> int main()
> {
> AS*pab=new AS();
> pab->b=4;
> pab->a=5;
> pab->a=pab->foo();
>
> ***********//Output result is incorrect only 4 //***********
>
> delete pab;
> }
>
> Why isn't the output 9 as it is supposed to be ?

It is 9 on my system, after changing "strt" to
"struct" and adding an actual output statement.
That goes to show you haven't given us the actual
code that fails.

Also note that what you are doing is assignment,
not initialization.

- J.

Jacek Dziedzic $B$N%a%C%;!<%8(B:
> Peter Liu wrote:
> > This simple code
> >
> > typedef strt B{
> > int b;
> > }BS;
> >
> > typedef struct A:B
> > {
> > int a;
> > int foo(){return a+b;}
> > }AS;
> >
> > int main()
> > {
> > AS*pab=new AS();
> > pab->b=4;
> > pab->a=5;
> > pab->a=pab->foo();
> >
> > ***********//Output result is incorrect only 4 //***********
> >
> > delete pab;
> > }
> >
> > Why isn't the output 9 as it is supposed to be ?
>
> It is 9 on my system, after changing "strt" to
> "struct" and adding an actual output statement.
> That goes to show you haven't given us the actual
> code that fails.
>
> Also note that what you are doing is assignment,
> not initialization.
>
> - J.

Sorry everyone, it works correctly, my mistake hehehhe.