Re: new syscall stub support for ia64 libc

[Jakub Jelinek <jakub at redhat dot com>]

On Fri, Oct 31, 2003 at 08:45:22AM -0800, David Mosberger wrote:
> >>>>> On Fri, 31 Oct 2003 08:01:14 +0100, Jakub Jelinek <jakub@redhat.com> said:
> 
>   Jakub> Cannot tcbhead_t's private field be reused for the sysinfo pointer
>   Jakub> actually on IA-64?
> 
> As long as we can make it appear at offsets -8, that would be OK.

It would be offset 8, not -8 actually.

>   Jakub> That way 32 bytes wouldn't have to be wasted at end of struct
>   Jakub> pthread, it would be at the same location in linuxthreads as
>   Jakub> well as NPTL build
> 
> That's not sufficient.  The offset must be the same across _all_ libcs,
> so that non-libc code can use the new syscall stubs as well.

I don't think it is a good idea to give access to glibc internals (which
these are) to outside code.  There is syscall(3) function for a reason.
Also, derefencing r13[-8] (or r13[8]) in various syscall stub macros
is not going to work if you run the program then against older glibc
and there won't be any symbol versioning which would catch it up.

	Jakub