Re: eb77.C

[Joe Buck <jbuck at Synopsys dot COM>]

> 
> > > Since the constructor for strstream is empty, this invokes undefined
> > > behaviour.
> > 
> > It is not empty, and it seems to me that it should not invoke
> > undefined behavior.
> 
> Look at this code from egcs/libio/strstream.h and tell be what
> strstream::strstram () does:
> 
> class strstream : public strstreambase, public iostream {
>   public:
>   strstream() { }
>	...
> };

It first calls strstreambase::strstreambase() and then calls
iostream::iostream().  It is not empty.  This is basic C++;
constructors for derived classes call those for base classes.

class strstreambase : virtual public ios {
	...
 protected:
    strstreambuf __my_sb;
	...
    strstreambase() { init (&__my_sb); }
	...
};