On Thu, Jul 13, 2017 at 05:10:33PM -0600, Jeff Law wrote: > >>>> 2. ABI mandates that *sp always contain a backchain pointer (ppc) > >>> > >>> In the ELFv2 ABI a backchain is not required. GCC still always has > >>> one afaik. I'll find out more. > >> Please do. I was under the impression it was mandated by the earlier > >> ABIs as well. If it isn't, then I don't think we can depend on it for > >> the older ABIs. > > > > I checked most ABIs, and all but ELFv2 require it. You can assume we > > require it everywhere (we do assume it currently, and there is no > > intention to change this). The statement in the ABI surprised me > > yesterday, sorry for panicking. > Y'all are the experts here. It would be advisable to get the ABI > documents tweaked if indeed we are going to rely on the existence of the > backchain as an implicit probe.
Yes, we'll deal with whatever is needed here, don't worry :-) Segher
