error message for extending type with coarray component

[Damian Rouson]

Gfortran developers,

Could someone please tell me whether the error message below is a compiler bug or a requirement of the Fortran 2008 standard? 

Damian


$ cat extend.f90 
type object
end type
type, extends(object) :: periodic
  real f[*]
end type
end 

$ gfortran -fcoarray=single extend.f90 
extend.f90:3.33:

type, extends(object) :: periodic
                                 1   
Error: As extending type 'periodic' at (1) has a coarray component, parent type 'object' shall also have one

$ gfortran --version
GNU Fortran (MacPorts gcc48 4.8-20121202_0) 4.8.0 20121202 (experimental)