[Bug debug/66688] [6 Regression] compare debug failure building Linux kernel on ppc64le

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66688

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #5)
> (In reply to Jakub Jelinek from comment #4)
> > Created attachment 37027 [details]
> > gcc6-pr66688.patch
> > 
> > I think this just went latent with those changes.  The problem I see is that
> > cleanup_control_flow_bb can be called before fixup_noreturn_call is
> > performed, and in that case can either find a noreturn call at the end of bb
> > if -g0 or can't if the noreturn call is followed by some debug stmts.  This
> > hunk fixes the case so that it is handled the same.
> 
> Hum, why not just s/gsi_last_bb/gsi_last_nondebug_bb/?

That is possible too, but IMHO you still want to remove the debug stmts at that
point, removing fallthru edge while keeping noreturn call in the middle of bb
is weird.  Plus there is the question what to do if the other stmt kinds the
function is looking for are followed by debug stmts.  I'd strongly hope they
aren't, so perhaps we can just assert in that case it is the last stmt.