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Subject: [Bug fortran/47024] New: [OOP] STORAGE_SIZE (for polymorphic types): Segfault at run time
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47024

           Summary: [OOP] STORAGE_SIZE (for polymorphic types): Segfault
                    at run time
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
                CC: janus@gcc.gnu.org


STORAGE_SIZE does not work for unallocated polymorphic types. However, the
Fortran 2008 standard allows them:

"A    shall be a scalar or array of any type. If it is polymorphic it shall not
      be an undefined pointer. If it has any deferred type parameters it shall
      not be an unallocated allocatable variable or a disassociated or
undefined
      pointer." (F2008, 13.7.160)

Note: The standard allows an unallocated polymorphic variable - as long as the
type does not have any deferred type parameter. Fortunately, CLASS(*) does not
seem to be allowed as "CLASS(*)" has no type.

Maybe one should cross check (e.g. at the J3 mailing list) to see whether the
proper result is the declared type or something else.


implicit none
type t
  integer :: a
end type t
type, extends(t) :: t2
  integer :: b
end type t2

class(t), allocatable :: y

print *, storage_size(y)/8 ! Expected:  "4"; in reality: segfault
end