From owner-sc22wg5@open-std.org Mon Mar 30 02:30:58 2009 Return-Path: X-Original-To: sc22wg5-dom7 Delivered-To: sc22wg5-dom7@www2.open-std.org Received: by www2.open-std.org (Postfix, from userid 521) id F16D3C178DA; Mon, 30 Mar 2009 02:30:57 +0200 (CET DST) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org Received: from ns.nag-j.co.jp (218-42-159-107.cust.bit-drive.ne.jp [218.42.159.107]) by www2.open-std.org (Postfix) with ESMTP id A7561C178D9 for ; Mon, 30 Mar 2009 02:30:43 +0200 (CET DST) Received: from 218-42-159-108.cust.bit-drive.ne.jp ([218.42.159.108] helo=[127.0.0.1]) by ns.nag-j.co.jp with esmtp (Exim 4.50) id 1Lo5NK-0003ea-3j for sc22wg5@open-std.org; Mon, 30 Mar 2009 09:29:14 +0900 Message-ID: <49D012B0.1020104@nag-j.co.jp> Date: Mon, 30 Mar 2009 09:30:40 +0900 From: Malcolm Cohen User-Agent: Thunderbird 3.0a1pre (Windows/2008022014) MIME-Version: 1.0 To: WG5 Subject: Re: (j3.2006) question about deallocation References: <49CACA36.5070104@nag-j.co.jp> <49CDEC08.8040403@sun.com> In-Reply-To: <49CDEC08.8040403@sun.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-sc22wg5@open-std.org Precedence: bulk Robert Corbett wrote: > Consider the code fragment > > MODULE M > . . . > TYPE BASE > INTEGER I > CONTAINS > FINAL SUBR1 > END TYPE > TYPE, EXTENDS(BASE) :: EXTENDED > CONTAINS > FINAL SUBR2 > END TYPE > . . . > END MODULE > > PROGRAM MAIN > USE M > TYPE(EXTENDED), POINTER :: P > TYPE(BASE), POINTER :: Q > . . . > ALLOCATE(P) > Q => P%BASE > . . . > DEALLOCATE(Q) > . . . > END > > Is the DEALLOCATE statement standard conforming? No. Q is not associated with the whole of the object allocated by P, but only the "base" component thereof. The answers that indicate otherwise are mistaken. Whether EXTENDED takes up more memory than BASE in some/most/all implementations is not relevant to the question. BASE is a part of EXTENDED, not the whole. It is certainly not prohibited for some implementation to actually have EXTENDED objects taking up more space than BASE (whether it is sensible is another matter). > ALLOCATE(P(1)) > Q => P(1) > DEALLOCATE(Q) Did we *really* say that in an official interpretation? Which one? Assuming we did, I share your disquiet about the overly simplistic reply to this other question, but they can be separated - if one accepts that arrays are just collections of elements. It's not clear to me that that's a good thing to do (rather the opposite in fact), but it is not quite the same question. Bill Long wrote (that it should be allowed and): > The type of the object being deallocated is BASE, and a final routine is > bound to the type, so I would say SUBR1 (only) is executed. > That answer is not consistent with the design of final subroutines, and not consistent with types. An object of type EXTENDED was allocated. To deallocate an object of type EXTENDED one must deallocate an object of type EXTENDED - this must be fundamental to the whole idea of derived types. As far as I am concerned there is no question - the program is not, and cannot reasonably be considered to be, standard conforming. Cheers, -- .......................Malcolm Cohen, Nihon NAG, Tokyo.