------- Comment #1 from burnus at gcc dot gnu dot org 2008-04-27 08:01 -------
gfortran's rejection is in line with g95, NAG f95, ifort, openf95, sunf95 and
ifort.
I think gfortran is right and the sequence (or bind(C)) attribute is needed.
The reason is the same as for the following program:
type my_t
integer :: x, y, z
end type my_t
type(my_t) :: tt
call foo(tt)
contains
subroutine foo(t)
type foo_t
integer :: x, y, z
end type foo_t
type(foo_t) :: t
end subroutine
end
foo_t and my_t are different, incompatible types without SEQUENCE. From that
point of view, it makes sense to reject your example.
Additionally, I think the following also applies to pointers. ("my_wwsptr" is
of a derived type [albeit with pointer attribute].)
"C589 (R558) If a common-block-object is of a derived type, it shall be a
sequence type (4.5.1) or a type with the BIND attribute and it shall have no
default initialization."
* * *
If one now adds "SEQUENCE", gfortran rejects it as there is a default
initialization; in principle this it can be allowed as the default
initialization does not happen for pointers to derived types (only for its
targets). However, I believe that C589 also applies in this case.
The such modified program is rejected by NAG f95, sunf95, openf95, g95 and
gfortran, but ifort accepts the program.
* * *
In conclustion, I think both error messages of gfortran are correct.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36058
