[Bug tree-optimization/42326] New: segfault in tree-data-ref.c with Graphite building 200.sixtrack

["janis at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

GCC trunk gets an internal compiler error when building SPEC CPU2000 test
200.sixtrack with "-O2 -floop-parallelize-all -fprefetch-loops-arrays" on
powerpc-linux, as demonstrated by this minimized testcase:

      subroutine phasad(t,i,ium)
      implicit none
      real t(5,4)
      integer i,l,ll,ium

      do l=1,2
        ll=2*l
        do i=1,ium
          t(i,ll-1)=t(i,ll-1)+t(i,ll)
        enddo
      enddo
      return
      end

elm3b149% /home/janis/tools/gcc-trunk-anonsvn/bin/gfortran -c -O2
-floop-parallelize-all -fprefetch-loop-arrays bug.f
bug.f: In function ?phasad?:
bug.f:1:0: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

The failure has existed since the large Graphite merge that introduced
-fgraphite-force-parallel which was later renamed to -floop-parallelize-all.

The segmentation fault occurs in initialize_matrix_A at tree-data-ref.c:1914
when A[index] has the value (lambda_vector) 0xa.


-- 
           Summary: segfault in tree-data-ref.c with Graphite building
                    200.sixtrack
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: janis at gcc dot gnu dot org
GCC target triplet: powerpc-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42326