J3/14-109
To:        J3 Members
From:      Stan Whitlock
Subject:   F2008 interp: Is ASYNCHRONOUS allowed with VALUE?
Date: 2014 January 25

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NUMBER: F03/0nnn
TITLE: Is the ASYNCHRONOUS attribute allowed with the VALUE attribute?
KEYWORDS: ASYNCHRONOUS, VALUE
DEFECT TYPE: Erratum
STATUS: J3 consideration in progress

QUESTION:

In the description of the VALUE attribute, [101:23-24] section 5.3.18p1,
constraint C558 disallows the VOLATILE attribute with the VALUE
attribute:

  "C558 An entity with the VALUE attribute shall not have the
        ALLOCATABLE, INTENT (INOUT), INTENT (OUT), POINTER, or
        VOLATILE attributes."

But there is no prohibition of the ASYNCHRONOUS attribute with the VALUE
attribute.  Should this combination also be disallowed?

ANSWER:

Yes, the combination of VALUE and ASYNCHRONOUS attributes should be
disallowed.  Edits are supplied to correct this omission.

Note that F2003 allowed this combination.  Therefore this change adds
an incompatibility between F2003 and F2008.  F2008 Corrigendum 1
modified [24:11+] section 1.6.2 "Fortran 2003 compatibility" to start
a list of incompatibilities between F2003 and F2008.  F2008
Corrigendum 2 expanded that list.  The edit below just adds to that
list.

EDITS to 10-007r1:

[24:11+] In section 1.6.2p1, after the paragraphs added by J3 standing
document 023, N1957 F2008 Corrigendum 2, add the paragraph:

  "Fortran 2003 permitted an entity with the VALUE attribute to have
   the ASYNCHRONOUS attribute;  that is not permitted by this part of
   ISO/IEC 1539."

[101:23-24] In section 3.5.18p1 in constraint C558:

  after "ALLOCATABLE," insert "ASYNCHRONOUS,"

The entire constraint should read:

  "C558 An entity with the VALUE attribute shall not have the
   ALLOCATABLE, ASYNCHRONOUS, INTENT (INOUT), INTENT (OUT), POINTER,
   or VOLATILE attributes."

SUBMITTED BY: Stan Whitlock

HISTORY: 14-xxx    m203  F08/nnnn Submitted

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