Re: [Swarm-Support] x86_64 and message forwarding

[Bill Northcott]

On 28/08/2006, at 10:04 AM, Marcus Daniels wrote:
> Bill Northcott wrote:
> > Marcus Daniels wrote:
> > > > Paul Johnson wrote: The objective C support with these new RPMs  
> > > > works fine. I did not test
> > > > the Java version.
> > > I know there are problems with Java message forwarding on x86_64,  
> > > but i386
> > > seems to works fine.
> >
> > Is this a problem with avcall/libffi?  I am trying to get libffi  
> > to work for Darwin x86 and x86_64 but I don't have a machine to  
> > test the latter.
> I can test on AMD64/Linux, but unfortunately there's more to it  
> than finding the right frame offsets.
>
> Traditionally, GCC compiles-in information on the call frame it  
> uses for Objective C calls.  For applications like distributed  
> objects or inter-language message forwarding, application code can  
> use those strings to understand the frame.
> For example, if you run "make check" in tests/defobj, on an AMD64  
> Linux system you'll get a failure that ends with
> m1: [1 0 0].  Just above that on the right, you'll see two copies  
> of the same string:
....... etc

Thanks for that.  I am still at the info gathering stage for x86-64  
Darwin.  As of today, Apple have not got around to posting sources  
for the current compilers or the updated x86-64 ABI documentation.  I  
imagine that with all the new products going out the door and Leopard  
to finish off, there are other priorities.  The 32 bit x86 ABI was  
very similar to Linux but not quite the same so I will have a go at  
that first.

I have found that they have been responsive to fixing behaviour in  
their compiler which differs from that of the FSF one.  So it is  
worth testing and filing bugs if we find it does not work.

Bill