initialization on a struct member fails

[Peter Liu]

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

[=?iso-8859-1?q?Erik_Wikstr=F6m?=]

On Jan 19, 3:46 pm, "Peter Liu" <[e-mail]>
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;
}

[Grizlyk]

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 !!!

[Jacek Dziedzic]

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.

[Peter Liu]

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. :-(