[tree-ssa] New g++/libstdc++ regressions with checking disabled.

[Jan Hubicka]

> 
> Folks,
> 
> One of these patches is exposing new regressions in the g++ and
> libstdc++ testsuites (at least not in x86-64, the others are still
> churning).
> 
> I haven't been able to see which one.  Could you help me out and see if
> it's not due to your patch?  I'm not getting these failures in
> enabled-checking testers.

This is exactly the same latent problem as exposed by the tail call
patch.  This time it reproduces without bootstrapping on unoptimized
compiler, so we have realistic chance to debug it out.

Honza