Another GLIBC build error with GCC6

[Steve Ellcey]

On Tue, 2015-08-18 at 19:18 +0200, Marek Polacek wrote:
> On Tue, Aug 18, 2015 at 10:13:00AM -0700, Steve Ellcey wrote:
> > On Tue, 2015-08-18 at 10:04 -0700, Paul Eggert wrote:
> > > Steve Ellcey wrote:
> > > > I put the old and new
> > > > code segments in a small test program and compiled it on MIPS (32 and 64
> > > > bit modes) and verified that the generated code was identical for both
> > > > versions in that setting.
> > > 
> > > That's good enough for me.  I installed the patch.
> > > 
> > > Wasn't there a similar problem with DT_EXTRATAGIDX?  See, for example:
> > > 
> > > https://sourceware.org/ml/libc-alpha/2015-07/msg00742.html
> > 
> > For some reason, I am no longer seeing this problem.  I don't see any
> > changes in GLIBC or GCC that look like they would have made this problem
> > go away so I am not sure what is going on.
> 
> If this is about shift overflow warnings:
> I've changed the -Wshift-overflow warning to not warn when left-shifting 1
> into the sign bit.  It caused way too much noise.  If you still want to see
> even those, use -Wshift-overflow=2.
> <https://gcc.gnu.org/ml/gcc-patches/2015-08/msg00617.html>
> 
> 	Marek

Yes, that was the issue.  It might still be worth cleaning up the
definition of this macro as was discussed in the email thread even
though we aren't getting warnings any more.  I will see if I can do that
sometime in the next few weeks.

Steve Ellcey
sellcey@imgtec.com