[Bug fortran/68153] New: ICE for intrinsic reshape with negative dim in effective shape

["gerhard dot steinmetz dot fortran at t-online dot de" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68153

            Bug ID: 68153
           Summary: ICE for intrinsic reshape with negative dim in
                    effective shape
           Product: gcc
           Version: 5.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gerhard.steinmetz.fortran@t-online.de
  Target Milestone: ---

This code with negative dimension(s) in shape sh :

$ cat z1.f90
program p
   integer, parameter :: sh(2) = [2, -2]
   integer, parameter :: a(2,2) = reshape([1, 2, 3, 4], sh)
   print *, a
end

$ gfortran -g -O0 -Wall -fcheck=all z1.f90
f951: internal compiler error: in gfc_simplify_reshape, at
fortran/simplify.c:5091

---

$ cat z4.f90
program p
   integer, parameter :: sh(2) = -2
   integer, parameter :: a(2,2) = reshape([1, 2, 3, 4], sh)
   print *, a
end

$ gfortran -g -O0 -Wall -fcheck=all z4.f90
f951: internal compiler error: in gfc_simplify_reshape, at
fortran/simplify.c:5091