[Bug middle-end/55555] [4.8 Regression] miscompilation at -O2 (tree-pre?)

[Joost.VandeVondele at mat dot ethz.ch]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55555

--- Comment #5 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> 2012-12-02 10:11:34 UTC ---
(In reply to comment #4)
> Hmm, this seems to be caused by
> Forced statement unreachable: pretmp_516 = coef_x[pretmp_515];
> Forced statement unreachable: pretmp_513 = coef_x[pretmp_512];
> Forced statement unreachable: pretmp_479 = coef_x[pretmp_478];
> 
> I am not exactly fortran guru. Can someone double check that there are no out
> of bounds accesses into these?
> 
> Honza

I'm pretty sure there are no out-of-bounds. In particular coef_x is easy to
check, it is only used as coef_x(:,lxp) where lxp is the loop bound 0..lp
consistent with its def. Of course maybe the FE does something inconsistent ?

Also this runs fine:

fortran -O0 -fsanitize=address PR55555.f90 ; ./a.out