[Bug fortran/57284] New: ICE with "find_array_spec: unused as (1)" in conjunction with size() intrinsic on class dummy parameter shape

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57284

            Bug ID: 57284
           Summary: ICE with "find_array_spec: unused as (1)" in
                    conjunction with size() intrinsic on class dummy
                    parameter shape
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bugs at stellardeath dot org

Created attachment 30119
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30119&action=edit
Minimal test case

I get an ICE for the following (valid?) minimal test-case involving a size()
intrinsic for a class() dummy argument:

> cat minimal.f90
module testmod
  type type_t
  end type type_t
  contains
  function foo(a, b) result(add)
    class(type_t), intent(in) :: a(:), b(size(a))
    type(type_t) :: add(size(a))
  end function
end module testmod
program p
  use testmod
end program
>
> ~/sys/bin/gfortran minimal.f90 
minimal.f90:10.9:

program p
         1
Internal Error at (1):
find_array_spec(): unused as(1)
>
> ~/sys/bin/gfortran --version
GNU Fortran (GCC) 4.9.0 20130514 (experimental)
Copyright (C) 2013 Free Software Foundation, Inc.

GNU Fortran comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of GNU Fortran
under the terms of the GNU General Public License.
For more information about these matters, see the file named COPYING


Here, ~/sys/bin/gfortran is a self-compiled gfortran from yesterday's trunk,
the ICE also happens with the gfortran 4.7.2 supplied with openSUSE:


> gfortran --version
GNU Fortran (SUSE Linux) 4.7.2 20130108 [gcc-4_7-branch revision 195012]
Copyright (C) 2012 Free Software Foundation, Inc.

GNU Fortran comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of GNU Fortran
under the terms of the GNU General Public License.
For more information about these matters, see the file named COPYING

> gfortran minimal.f90 
minimal.f90:10.9:

program p
         1
Internal Error at (1):
find_array_spec(): unused as(1)