[J3] Does LHS of a pointer assignment have the POINTER attribute?

[Daniel C Chen]

Thanks Malcolm,

Part of the question is if fp(1:) has the POINTER attribute. From your
explanation, I suppose the answer is "NO", correct?

Thanks,


Daniel Chen

XL Fortran Development, Fortran Standard Representative
IBM Toronto Software Lab
Phone: 905-413-3056
Tie: 969-3056
Email: cdchen at ca.ibm.com



From:	"Malcolm Cohen via J3" <j3 at mailman.j3-fortran.org>
To:	"'General J3 interest list'" <j3 at mailman.j3-fortran.org>
Cc:	"Malcolm Cohen" <malcolm at nag-j.co.jp>
Date:	2021-10-07 08:00 PM
Subject:	[EXTERNAL] Re: [J3] Does LHS of a pointer assignment have the
            POINTER attribute?
Sent by:	"J3" <j3-bounces at mailman.j3-fortran.org>



>fp(1:) can appear as the LHS of a pointer assignment, does it mean fp(1:)
have the POINTER attribute? If so, case 3 is not conforming as POINTER is
not interoperable. You are confusing two different things. In fp(1:) =>
target ‍‍‍‍‍‍
>fp(1:) can appear as the LHS of a pointer assignment, does it mean fp(1:)
have the POINTER attribute? If so, case 3 is not conforming as POINTER is
not interoperable.

You are confusing two different things. In
   fp(1:) => target
the “(1:)” are “( lower-bounds-expr : )”

In the case of an actual argument, the “(1:)” are “( section-subscript-list
)”.

Similarly, in
   REAL X(2,3,4)
the 2, 3 and 4 are upper bounds expressions, *and not subscripts*.

It should be obvious that the contexts are different, and in different
contexts, identical character sequences may have different meaning. In
particular, array bounds are not subscripts and vice versa.

I note that the “conforming/not conforming” question is being answered via
interp, and the current answer (not yet fully settled) is that all your
cases are conforming.

Cheers,
--
..............Malcolm Cohen, NAG Oxford/Tokyo.

From: J3 <j3-bounces at mailman.j3-fortran.org> On Behalf Of Daniel C Chen via
J3
Sent: Friday, October 8, 2021 1:57 AM
To: j3 at mailman.j3-fortran.org
Cc: Daniel C Chen <cdchen at ca.ibm.com>
Subject: [J3] Does LHS of a pointer assignment have the POINTER attribute?



Consider the following code:

use iso_c_binding
integer, pointer :: fp(:)
integer, target :: tar(10)
fp => tar
fp(1:) => tar
print *, c_sizeof(fp(:))   ! case 1: conforming
print *, c_sizeof(fp)      ! case 2: not conforming
print *, c_sizeof(fp(1:))  ! case 3: ??
end

fp(1:) can appear as the LHS of a pointer assignment, does it mean fp(1:)
have the POINTER attribute? If so, case 3 is not conforming as POINTER is
not interoperable.

Thanks,

Daniel Chen

XL Fortran Development, Fortran Standard Representative
IBM Toronto Software Lab
Phone: 905-413-3056
Tie: 969-3056
Email: cdchen at ca.ibm.com




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