[Bug fortran/89033] New: gfortran accepts invalid code in select type construct with pointer assignment

[mscfd at gmx dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89033

            Bug ID: 89033
           Summary: gfortran accepts invalid code in select type construct
                    with pointer assignment
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mscfd at gmx dot net
  Target Milestone: ---

The code below should be invalid, as the selector x has attribute "target" but
not "pointer" inside the select type block (2008 draft, 8.1.3.3). The code
compiles, but it gives a suprising output, namely x is still associated,
despite the accepted "x => null()" line.

program select_type_ptr

implicit none

type t
   integer :: i = 1
end type t

class(*), pointer :: x
type(t), pointer :: y

allocate(x, source = t(3))

select type (x)
type is (t)
   y => x
   x => null()
end select

print *, associated(x), associated(y)
print *, y%i

end program select_type_ptr