Re: virtual table off by three problem

[Marc Brett]

Me too.
We're getting the same behaviour with g++ 2.95.2 and Redhat 6.2,
SGI workstation with single processor Pentium III.
Trying to recompile with g++ 3.0.2, but this may take some time.

Would be interested to hear if you make any progress.

Aubrey Holland <address@hidden> wrote:
> In one of my libraries, I have a rather deep inheritance tree where
> the classes in this tree contain quite a few virtual functions.  I
> have noticed recently that there seems to be a problem with the
> virtual tables that get created for some of these classes. 
> Specifically, when I try to call one of the virtual methods in this
> class, the result is that I get a call to the virtual method that is
> three virtual methods down in the header file.  I.e. in the following
> overly-simplified example, a call to a() would result in d() actually
> being called.  This happens regardless of where I place the function
> in the header file... the third one down is always called.

> class example
> {
>     virtual void a();

>     void nonvirtual();

>     virtual void b();
>     virtual void c();
>     virtual void d();
> };

> I saw the following previous similar posting, but it seems to indicate
> the the bug is already fixed:

> http://groups.google.com/groups?q=g%2B%2B+virtual+table+off+by&hl=en&selm=Pine.OSF.3.91j.950911160602.5228N-100000%40saul6.u.washington.edu&rnum=3

> I'm working on trying to reproduce this in a smaller, more portable
> example program but haven't had much luck as of yet.

> Sysyem info:

> Dual processor Dell Workstation, running Pentium Xeon processors.
> RedHat 7.2
> gcc and g++ 2.96-98

> TIA,
> Aubrey Holland

-- 
Marc Brett  +44 20 8560 3160            WesternGeco
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