To:       J3                                                    08-162
From:     Jim Xia
Subject:  Comment: allocatable coarray and non-coarray allocatable dummy

Date: 2008 April 25
References: J3/08-007r2 (WG5/N1723)


DISCUSSION:
It seems that N1723 allows an allocatable coarray to be associated
with a non-coarray allocatable dummy. Consider the following sample
program

real, allocatable :: x(:)[:]
call sub (x)                  !<-- this should be disallowed
...
subroutine sub (y)
  real, allocatable :: y(:)
...
end subroutine

Since subroutine sub expects a non-coarray allocatable dummy, it could
allocate or deallocate the dummy argument, which causes implicit
synchronizations on the actual argument. This call should not be allowed.

EDITS:

[292] After the first sentence in the second paragraph of 12.5.2.6
      Allocatable dummy variables, insert a new sentence

      "The actual argument shall be a coarray if and only if the
       associated dummy argument is a coarray."


SUBMITTED BY: Jim Xia

HISTORY: m184 Submitted