J3/16-156 To: J3 From: John Reid and Bill Long Subject: Team variables Date: 2016 February 03 1. Introduction Prompted by queries from Malcolm Cohen, we have been considering whether the text in 5.3 and 5.6 of TS 18508 should be altered on its way to the draft new standard. We express suggested changes as edits to TS 18508, but we are not proposing that a corrigendum be issued. Our aim is simply to make sure that the new standard expresses the aims of WG5 clearly. 2. Edit to 5.6 [13:5-7] Change the sentence "The values ... initial team." to "The shall be defined with a value that represents an ancestor team, the current team, or a team formed from the current team. The values of the s on the active images of the team shall all represent the same team." Reasons a. The present text does not make it clear that the team may be an ancestor, the current team, or a team that is part of the current team. b. There are no restrictions on assignments of team variables or on associations between team variables. We therefore need to require that the values of the team variables on each image of the team specify the same team. This was done by the old text, but it is clearer to say this directly. 3. Edit to 5.3 [11:17-19] Change the sentence "The values ... initial team." to "The values of the s on the active images of the current team shall be those of team variables defined by execution of the same FORM TEAM statement on all active images of the current team." Reasons a. The present text is wrong because it allows the team within a CHANGE TEAM construct to be the initial team when the current team is a proper subset of the images. It was intended that every CHANGE TEAM statement be preceded by a FORM TEAM statement that formed the team. For example, N1983 had "The value of the shall have been formed by executing a FORM SUBTEAM statement." b. Whereas for SYNC TEAM, we need to require that the present values of the team variables on the images specify the same team, here we need to ensure that they come from the same formation of teams. 4. Note on CHANGE TEAM Note that the TS does not disallow the team of a CHANGE TEAM statement to have the same set of active images as the current team. This allows a different set of image indices to be used inside the change team construct. It might also occur "accidentally" because of the failure of the images that would normally occupy another team.