J3/17-213r2
To: J3
From: John Reid & Reinhold Bader & Bill Long
Subject: Comment 76
Date: 2017 October 17

Discussion:
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The image selectors in C.6.7 are invalid because they use TEAM_NUMBER
but reference a coarray that is an associating entity. This is not
permitted by the rules in 9.6.

We could change the image selectors in C.6.7 to reference the original
coarray. The lines would become
      A (:, 10) = A (:, 1)[1, 1, TEAM_NUMBER=UR]
and
      A (:, 10) = A (:, 1)[2, 1, TEAM_NUMBER=UR]
While the revised statements are simple, data exchanges across other
boundaries would be awkward because we are using the cobounds [4,*]
to address a coarray on a 2x2 grid. We believe that it was always
intended to allow an associating entity in an image selector that uses
TEAM_NUMBER, that is, for the example to work. A change to 9.6 will
allow this. The symmetric memory aim (NOTE 5.11) is met because
[188:12] says "Each selector shall be an established coarray when the
CHANGE TEAM statement begins execution.".

Edits to 17-007r2:
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[139:33] In 9.6 Image selectors, para 3, after "ancestor of the current
team", add ", or an associating entity of the CHANGE TEAM construct."