To: J3 13-288r1 From: Reinhold Bader Subject: Synchronization of CHANGE TEAM and END TEAM Date: 28 June 2013 References: N1967, N1971 Discussion: ~~~~~~~~~~~ N1967 presently specifies that for both the CHANGE TEAM and END TEAM statements, synchronization of all images of the parent team is required, implying that all these images are obliged to execute these statements. This paper relaxes the requirement, replacing it by one that synchronization only applies to individual subteams in the decomposition established by FORM SUBTEAM. Edits to N1967: ~~~~~~~~~~~~~~~ [9:5-6] Delete "Except by ... the team." [10:11-16] Replace paragraph by "The CHANGE TEAM and END TEAM statements are image control statements. When a CHANGE TEAM statement is executed, there is an implicit synchronization of all images of the team identified by ; the executing image shall be a member of this team. On each image of the team, execution of the segment following the statement is delayed until all the other images of the team have executed the same statement the same number of times. When a CHANGE TEAM construct completes execution, there is an implicit synchronization of all images in its team. On each image of the team, execution of the segment following the END TEAM statement is delayed until all the other images of the team have executed the same construct the same number of times." Edits to the standard (TS section 8): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~[...] denotes an addition to existing text. [27:18+] Add this new edit to 8.5 Edits to Clause 8 {In 8.5.4 SYNC IMAGES statement, edit paragraphs 1 - 3 as follows} "If is an array expression, the value of each element shall be positive and not greater than the number of images ~[of the current team], and there shall be no repeated values. If image-set is a scalar expression, its value shall be positive and not greater than the number of images ~[of the current team]. An that is an asterisk specifies all images ~[of the current team]."