[Bug fortran/46100] New: Non-variable pointer expression as actual argument to INTENT(OUT) non-pointer dummy

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46100

           Summary: Non-variable pointer expression as actual argument to
                    INTENT(OUT) non-pointer dummy
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: bur...@gcc.gnu.org


Reported at c.l.f by Thomas Jahns:
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread
/a64e2f255466a87a

GNU Fortran (and most other compilers) reject passing a non-variable pointer
expression as actual argument to an INTENT(OUT)/INTENT(INOUT) non-pointer dummy
argument.

The reason for rejecting is that the pointer expression (i.e. a function
returning a pointer) itself is not definable. However, I believe now that it
the code is valid. Thus, only if the argument were a pointer dummy or the
expression were not a pointer expression, it would be invalid.

Example:

call one (two ())
contains
  subroutine one (x)
    integer, intent(inout) :: x
  end subroutine one
  function two ()
    integer, pointer :: two
    allocate(two)
  end function two
end

Error message:

call one (two ())
          1
Error: Non-variable expression in variable definition context (actual argument
to INTENT = OUT/INOUT) at (1)