To: J3                                                       J3/12-155
Subject: Definition of "context that requires its shape"
From: Van Snyder
Date: 2012 June 11

1. Introduction
---------------

5.3.8.5p4 prohibits an assumed-size array to appear in a context that
requires its shape.  There is no explicit definition of that.
Requirements on assumed-size arrays that are based on the requirement to
know its shape are scattered throughout.  It would be better to put them
in one place in the next revision.

2. Edits for next revision
--------------------------

[95:36-37 C534] Replace Constraint 534

"C534 An assumed-size array shall not

  o have the INTENT(OUT) attribute if it is polymorphic, finalizable, of
    a type with an allocatable ultimate component, or of a type for
    which default initialization is specified, {old C534}
  o have the VALUE attribute, {C557}
  o be a namelist group object, {C585}
  o appear as a whole array reference in an executable construct or
    specification expression unless it is an actual argument in a
    procedure reference that does not require its shape, {6.5.2p2}
  o appear as an array section reference in which the final subscript
    triplet does not include a second subscript, {5.3.8.6p5, C627}
  o be a whole array <designator> that is a <primary>, {C702}
  o be a whole array <variable> in an assignment statement, {C709}
  o be an <input-item> that is a whole array, {C932}
    {This might not be necessary in light of "appear as a whole array
    reference ... above}
  o be a polymorphic actual argument if the referenced procedure does
    not have explicit interface, {explicitly solves the problem
    addressed by f08/0067}
  o be a polymorphic actual argument if the corresponding dummy argument
    is not polymorphic and is not either a scalar or an explicit-shape
    array, {explicitly solves the problem addressed by f08/0067}
  o be a whole array actual argument corresponding to an assumed-shape
    dummy argument, {12.5.2.4p14}
  o be the SOURCE argument in a reference to the SHAPE intrinsic
    function, {6.5.2p2, 7.1.11p2(9)(b)(i)}
  o be the ARRAY argument in a reference to the SIZE or UBOUND intrinsic
    function, unless the DIM argument appears, {6.5.2p2,
    7.1.11p2(9)(b)(i)}
  o be the X argument of the C_SIZEOF function from the ISO_C_BINDING
    intrinsic module. {7.1.11p2(9)(b)(i)}

NOTE 5.12a
  The contexts prohibited by C534 either require the shape of an
  assumed-size array, or imply its shape might be required in some
  context.
"

3. Possible additional edits
----------------------------

The following are redundant as a result of the replacement of C534, and
could be deleted:

[96:15 5.3.8.5p4] Delete "An assumed-size array shall not appear in a
context that requires its shape."

[96:18-19 5.3.8.6p5] Delete "The upper bound shall not be omitted from a
subscript triplet in the last dimension." This could be deleted in any
case since it duplicates C627.

[101:21 C557] Delete "an assumed-size array or".

[111:10 C585] Delete C585.

[122:4-5 C627] Delete C627.

[133:26 C702] Delete C702.

[153:5 C713] Delete C713.

[217:12 C932] Delete C932.

[294:33-34 12.5.2.4p14] Delete "; the actual argument ... substring
designator)".  The parenthetical requirement can be deleted in any case,
since it is implied by "appearance as an array section reference in
which the final subscript triplet does not include a second subscript."