Re: Strange behaviour in C++...

["Christopher R. Jones" <cj@interlog.com>]

I am puzzled at the lack of attention this thread has received.  There is
obviously some strange behavior with gcc 2.95.1 on Linux (at least Redhat
5.2):

Using a 180 Pentium Pro:
>From Solairs Intel, gcc 2.95.1, built with gcc 2.8:
Alfa 1=42
Alfa 2=42
BetaAlfa=42
Alfa 1=47
Alfa 2=47
GammaAlfa=47
AlfaGammaAlfa=47

>From Linux Redhat 5.2, gcc 2.95.1, built with egcs 1.1.2:
Alfa 1=42
Alfa 2=42
BetaAlfa=42
Alfa 1=47
Alfa 2=134580833
GammaAlfa=47
AlfaGammaAlfa=47

At 04:54 PM 8/24/99 +0200, Fredrik Öhrström wrote:
>
>The code below compiled with 2.95.1 (19990816) 
>(on a RedHat 5.2 system i386) produces:
>
>Alfa 1=42
>Alfa 2=42
>BetaAlfa=42
>Alfa 1=47
>Alfa 2=134580865
>GammaAlfa=47
>AlfaGammaAlfa=47
>
>Shouldn't Alfa 2 be 47 in the second creation?
>
>Cheers
>Fredrik
>
>---------------------------------------------------------
>
>
>#include<iostream.h>
>
>struct Alfa
>{
>        virtual int alfa() = 0;
>};
>
>struct Beta
>{};
>
>struct Gamma
>{};
>
>struct Alfa_i : public virtual Alfa                
>{
>        int a;
>
>        Alfa_i (int aa) : a (aa)
>        {
>        }        
>        
>        int alfa ()
>        {
>                return a;
>        }
>};
>
>struct Beta_i : public virtual Beta,
>                public Alfa_i
>{
>        Beta_i (int bb) : Alfa_i (bb)
>        {
>                cerr << "Alfa 1=" << alfa ()<< endl;
>                Alfa *a = this;
>                cerr << "Alfa 2=" << a->alfa ()<< endl;                
>        }
>};
>
>struct Gamma_i : public virtual Gamma,
>                 public Beta_i
>{
>        Gamma_i (int cc) 
>                        : Beta_i (cc)
>        {}
>};
>
>  
>int main ()
>{
>        Beta_i *b = new Beta_i (42);
>        cerr << "BetaAlfa=" << b->alfa() << endl;
>
>        Gamma_i *g = new Gamma_i (47);
>        cerr << "GammaAlfa=" << g->alfa() << endl;
>
>        Alfa *a = g;
>        cerr << "AlfaGammaAlfa=" << a->alfa() << endl;        
>}
>
>
>
>
>
Christopher R. Jones, P.Eng.
14 Oneida Avenue
Toronto, Ontario M5J 2E3
Tel. 416 203-7465
Fax. 416 203-3044
Email cj@interlog.com




Christopher R. Jones, P.Eng.
14 Oneida Avenue
Toronto, Ontario M5J 2E3
Tel. 416 203-7465
Fax. 416 203-3044
Email cj@interlog.com