[Bug fortran/45859] New: [Coarray, F2008, IR] Rejects valid actuals to coarray dummies

["burnus at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45859

           Summary: [Coarray, F2008, IR] Rejects valid actuals to coarray
                    dummies
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
            Blocks: 18918,39627


The discussion has started at
   http://j3-fortran.org/pipermail/j3/2010-September/003862.html
and lead to the following interpretation request (no link as the mail archive
lags behind).

The program
   interface
      subroutine sub (x)
         real x(10)[*]
      end subroutine
   end interface
   real :: x(100)[*]
   call sub (x(10))
   end

is supposed to be valid according the following IR. A modified program which
uses
   call sub (x(10:))
is unambiguously valid. However, both programs are rejected by:

   call sub (x(10))
              1
Error: Actual argument to 'x' at (1) must be a coarray and thus shall not have
an array designator

------------------------------------------------------
To: J3                                                     10-xxx
From: John Reid
Subject: F2008 interp re sequence association for coarrays
Date: 2010 October 1

NUMBER: F08/xxxx
TITLE:  Sequence association for coarrays
KEYWORDS: sequence association, coarrays
DEFECT TYPE: Erratum
STATUS: J3 consideration in progress

QUESTION:

Was the text in 12.5.2.8:
"If the dummy argument is an array coarray that has the CONTIGUOUS 
attribute or is not of assumed shape, the corresponding actual argument 
shall be simply contiguous." 
intended to disallow sequence association for coarrays, as 
illustrated by the example

   interface
      subroutine sub (x)
         real x(10)[*]
      end subroutine
   end interface
   ...
   real :: x(100)[*]
   ...
   call sub (x(10)) 

ANSWER:

No. This restriction contradicts 12.5.2.4 paragraph 13, which allows 
the example program. An edit is supplied to correct this.

EDIT:

In 12.5.2.8 Coarray dummy variables, at the end of paragraph 2, 
add "or an element of a simply contiguous array".

SUBMITTED BY: John Reid