[fpc-devel] Passing parameters through the stack to interfaces

Joost van der Sluis joost at cnoc.nl
Thu Aug 5 17:16:55 CEST 2010

On Thu, 2010-08-05 at 17:36 +0400, Sergei Gorelkin wrote:
> Joost van der Sluis пишет:
> > ...
> > I don't know what's the best way to fix this.

> > 2: See if we can let the caller do the
> > interface-pointer-to-class-pointer conversion. That way the wrapper is
> > not necessary anymore. Leads to somewhat faster code, though less
> > compact. But this is only possible if the caller has enough information
> > to do the conversion. I'm not sure if that's the case.
> > 
> Unfortunately, the caller cannot make any assumptions about the implementor's
> internal structure. The callee side may as well be a non-Pascal code.

The caller doesn't have to make any assumptions. It passes the 'self'
pointer on the stack, since it knows that the callee wants that. 

But I see now that this can't work. Because the 'callee' expects the
interface-pointer, not the class-pointer. And we can change that for
pascal-callee's, but not for others.

So it comes down on the same thing: this option can't work. I'll try
option 1 as you and Jonas pointed out that shoudn't be a problem.


More information about the fpc-devel mailing list