Subject: Re: RETURN_IN_MEMORY
To: <>
From: David Laight <david@l8s.co.uk>
List: port-arm
Date: 08/29/2002 11:42:50
On Thu, Aug 29, 2002 at 09:54:27AM +0100, Richard Earnshaw wrote:
> > On Wed, Aug 28, 2002 at 07:42:19PM +0100, Chris Gilbert wrote:
> > 
> >  > One question, is this going to change/break any ABI's?  I suspect not, but just a thought, and wanted to be sure.
> > 
> > No, everything in the NetBSD tree, at least, should be okay.  But it's
> > gotta be fixed before 1.6 goes out the door.
> 
> Even if it did break the ABI, it has to be fixed.  Otherwise you can never 
> safely return a variable sized struct of more than 16 bytes without 
> trashing saved registers.

Is there a trap to ensure that the size of a returned structure
is known to the calling program?

Otherwise the caller won't know whether it is large or small and
will generate the wrong call sequence.

(or have I missed which bit of the language we are talking about)


	David

-- 
David Laight: david@l8s.co.uk