[Bug middle-end/57393] [4.9 Regression] error: definition in block 4 follows the use / internal compiler error: verify_ssa failed

["Joost.VandeVondele at mat dot ethz.ch" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57393

--- Comment #29 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> ---
(In reply to Joost VandeVondele from comment #28)
> OK, with only the patch mentioned above applied all testcases now pass. I
> think this patch should be posted to gcc-patches for review, if you haven't
> done yet. Thanks!

Unfortunately, more testing with this patch applied now leads to this:

> gfortran -g -O2 -c  bug.f90
bug.f90: In function âmp_alltoall_z11vâ:
bug.f90:1:0: internal compiler error: Segmentation fault
   SUBROUTINE mp_alltoall_z11v ( sb, scount, sdispl, rb, rcount, rdispl, group
)
 ^
0x9d222f crash_signal
    ../../gcc/gcc/toplev.c:335
0xb11ac7 assign_uids_for_stmts_before
    ../../gcc/gcc/tree-ssa-reassoc.c:1968
0xb128bb negate_value
    ../../gcc/gcc/tree-ssa-reassoc.c:3410
0xb1b123 break_up_subtract
    ../../gcc/gcc/tree-ssa-reassoc.c:3460
0xb1b123 break_up_subtract_bb
    ../../gcc/gcc/tree-ssa-reassoc.c:3801

> cat bug.f90
  SUBROUTINE mp_alltoall_z11v ( sb, scount, sdispl, rb, rcount, rdispl, group )
    COMPLEX(kind=8), DIMENSION(:), INTENT(IN)        :: sb
    INTEGER, DIMENSION(:), INTENT(IN)        :: scount, sdispl, rdispl, rcount
    COMPLEX(kind=8), DIMENSION(:), INTENT(INOUT)     :: rb
    rb(rdispl(1)+1:rdispl(1)+rcount(1))=sb(sdispl(1)+1:sdispl(1)+scount(1))
  END SUBROUTINE mp_alltoall_z11v