[Bug tree-optimization/122456] [16 regression] LTO+profiledbootstrap failure on aarch64 since r16-4604-g8b9cd6490ce507

[amacleod at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122456

--- Comment #16 from Andrew Macleod <amacleod at redhat dot com> ---
(In reply to Andrew Pinski from comment #15)
> (In reply to Andrew Macleod from comment #13) 
> > There is also a second patch coming next which makes a minor tweak to the
> > debug output in the derived class...  and voila.. that makes the trap go
> > away!!!   Again, there is no real functional change.
> 
> That would make it seems like the code you added is being miscompiled and
> not your code causing the miscompiling directly. Figuring that out with LTO
> and PGO is much much harder.

yes. I think it merely uncovers something latent elsewhere. It seems unlikely
to be the new VRP code itself since the problem comes and goes without it
changing.   Im still looking to see if I can locate anything related to the
change which may help narrow things down too.