ISO/IEC JTC1/SC22/WG5 N2109 Minutes of Meeting of ISO/IEC JTC1/SC22/WG5 Hosted by INCITS/PL22.3, the US Member Body for JTC1/SC22 in Boulder, CO, USA June 6-10, 2016 List of Participants: John Reid (JKR Associates, UK) convenor Dan Nagle (NCAR, USA) PL22.3 chair Reinhold Bader (Leibniz Supercomputing Centre, Germany and DIN) Daniel Chen (IBM, Canada) Tom Clune (NASA, USA) Malcolm Cohen (NAG, UK) Bob Corbett (Oracle, USA) Steve Lionel (Intel, USA) Bill Long (Cray, USA) Nick Maclaren (University of Cambridge, UK) Lorri Menard (Intel, USA) Toon Moene (Gnu Fortran, Netherlands) David Muxworthy (British Standards Institution, UK) Craig Rasmussen (University of Oregon) (Monday to Thursday) Damian Rouson (Sourcery Inc, USA) (Monday to Thursday) Anton Shterenlikht (University of Bristol, UK) (Monday to Thursday) Van Snyder (Caltech/JPL, USA) Masayuki Takata (Edogawa University, Japan) Stan Whitlock (Intel, USA) Visitors: Danny Abukalam (Codethink, UK) (Wednesday and Thursday) Keith Bierman (Emeritus member of PL22.3, USA) (Wednesday) Walt Brainerd (Emeritus member of PL22.3, USA) (Wednesday) James van Buskirk (Independent Consultant, USA) (Wednesday) Srinath Vadlamani (Para Tools, Inc) (Friday) Notes: 1. This was a joint meeting of SC22/WG5 and INCITS/PL22.3. These minutes record only the parts of the meeting in WG5 mode. 2. WG5 papers are referenced as Nnnnn. They are available from http://www.nag.co.uk/sc22wg5/docs.html 3. INCITS/PL22.3 is abbreviated throughout to PL22.3 and its papers are referenced as J3/16-nnn. They are available from http://www.j3-fortran.org/ 1. Opening of the Meeting The meeting opened at 08:30 on Monday, June 6th 2016. 2. Opening business 2.1 Introductory remarks from the Convenor The convenor welcomed participants, especially Anton Shterenlikht who was attending WG5 for the first time. 2.2 Welcome from the Host Dan Nagle welcomed participants on behalf of INCITS and NCAR. 2.3 Local arrangements Dan Nagle described local arrangements and invited participants to dinner at Ted's Montana Grill restaurant on the Wednesday evening. 2.4 Appointments for this meeting The drafting committee was Reinhold Bader, Daniel Chen, Toon Moene, David Muxworthy (chair), Steve Lionel and Masayuki Takata. David Muxworthy acted as secretary and John Reid as librarian. 2.5 Adoption of the agenda [N2105] The agenda was adopted, subject to the amendment that there would be a 30 minute presentation on coarrays on the Tuesday morning. 3. Matters arising from the minutes of the London 2015 Meeting [N2068] There were no items not otherwise on the agenda. 4. Status of London 2015 Resolutions [N2077] The action in resolution L10, that the convenor should provide a document describing the reasons why WG5 did not apply for a new project to develop a TS on Units of Measure in Fortran, was still to be completed. With regard to resolution L7, the fourth corrigendum for Fortran 2008 had been submitted to ITTF but not yet published. JTC1 procedures stated that no more than two corrigenda should be published and that corrigenda should not normally be used for standards more than three years old. The preferred JTC1 procedure was to issue an updated standard containing only corrections. With regard to resolution L11, participants were asked to consider possible locations for a meeting in 2019. 5. Reports 5.1 SC22 Matters (Convener) John Reid said he intended to submit a new work item proposal for the revised standard at the SC22 meeting in September. Revised ISO Directives would require wording and format changes in the document. 5.2 National Activity Reports Canada: SCC had voted to confirm the Fortran base language. They had noticed that WG5 had not created a work item for the next standard revision and they had informed WG23 that there would be a revision of the vulnerability document for Fortran. Germany: Reinhold Bader was currently the only DIN member active in the Fortran area. A user questionnaire at LRZ on current and future HPC needs showed that on their Tier-1 system Fortran was still a majority language with respect to both code bases and cycles; however many codes were using mixed language programming. Japan: The Fortran working group in Japan had ten members. It was still preparing the Japanese version of Fortran 2008. More time was needed. Netherlands: The Programming Languages Committee of NEN, which had members for C, C++, Cobol and Fortran, had been disbanded. Toon Moene continued as an individual expert member of WG5. UK: A report was in N2104. US: The main activity was that of PL22.3. 5.3 Report from Primary Development Body (INCITS/J3 Chair) This was covered elsewhere in the agenda. 5.4 Reports from other Development Bodies (Editors/Heads) TS 18508 "Additional Parallel Features in Fortran" having been published, there were currently no contributing development bodies. 5.5 Liaison Reports: NCITS/J11 (C): Dan Nagle The Cplex effort was reaching maturity and was being forwarded to the C committees for inclusion in a future C standard. It appeared to be little more than OpenMP-style parallelism. MPI: Bill Long There was to be an MPI Forum meeting in this same week. It would be mainly in new feature mode for the next revision. Potentially interesting features were fault-tolerance progress, and InfoHints standardization for help with optimization. UPC: Damian Rouson The UPC language was stable and there was not a great deal of activity currently. IFIP/WG2.5: Van Snyder There was to be a meeting in Oxford in August, to be followed by a workshop. OpenMP: Bill Long The OpenMP language committee were to release a Technical Report at Supercomputing 2016, and they were preparing changes to the specification for that TR, and also for the OpenMP 5.0 release to follow (in 2017 or 2018). New facilities since February specific to Fortran were: - allow array sections in reduction clause for Fortran. - use "allocated" or "unallocated" to refer to allocation status in spec. - clarify usage of array sections with vector subscripts in map, to, from, depend, and reduction clauses. - indicate the references to whole arrays in target region is unspecified if only a partial array section was mapped. Other changes in the works: - [CLARIFICATION] If a Fortran pointer appears in a firstprivate clause, both the dope vector and the target should be privatized. - [CLARIFICATION] disallow common blocks on depend and linear clauses. - [NEW] allow function pointers in declare target. Some other topics being discussed were: - Clarify handling of Fortran pointers/allocatables in target, target data, and target update constructs. - Whether to clarify when compiler may generate copyin/copyout code at callsites where shared variables are passed in. The committee thought keeping this implementation-defined was appropriate (they believe this to be an issue to be clarified by Fortran, not OpenMP), and that users should consult their vendor as necessary. - Interaction between OpenMP memory model and C11/C++11 memory model. Discussion on interaction with Fortran coarrays memory model would be deferred (the committee was focusing on completing F2003 support for 5.0). WG9 (Ada): Van Snyder There was to be a meeting the following week. There was a proposal to revise Fortran interoperability. WG23 (Vulnerabilities): Dan Nagle The draft Fortran Annex needed to be updated to accommodate newly defined vulnerabilities. This work was proceeding but with low priority. 6. Review of the current draft of the next revision. From this point in the meeting the detailed review of the draft of the revised standard proceeded in PL22.3 mode. [PL22.3 plenary and subgroup sessions from 09:20 to 17:10] The meeting adjourned at 17:10 .......................................................................... Tuesday The meeting resumed at 08:30. Craig Rasmussen presented the paper "CAFe: A Unified PGAS Programming Model for Heterogeneous Computing" by Craig Rasmussen, Soren Rasmussen, William Dumas (all University of Oregon), Matt Sottile (Galois Inc) and Dan Nagle (NCAR). The slides are in document N2111. The presentation was also attended by two NCAR staff and was followed by general discussion. [PL22.3 plenary and subgroup sessions from 09:20 to 17:00] John Reid advised that drafts for the revised WG5 Strategic Plan (N2106) and the WG5 Report to SC22 for 2016 (N2107) were available and requested members to review them. [PL22.3 plenary session from 17:05 to 17:10] The meeting adjourned at 17:10 ........................................................................... Wednesday The meeting resumed at 08:30. Visitors Danny Abukalam and James van Buskirk were introduced. It was noted that Philip Sharp, a new member from New Zealand, was unable to attend but planned to attend in 2017. There was a short discussion about the 2019 meeting possibly being held in Japan. [PL22.3 plenary and subgroup sessions from 09:20 to 11:30] An official group photograph was taken. There was a gap in the formal agenda to allow for a tour of NCAR and to allow NCAR staff to discuss programming problems with WG5 members. There was a short discussion on the draft revised WG5 Strategic Plan. [PL22.3 plenary session from 17:05 to 17:10] The meeting adjourned at 17:10 and was followed by the meeting social event at Ted's Montana Grill, Boulder. ........................................................................... Thursday The meeting resumed at 08:30. Members were invited to examine a draft of the resolutions. [PL22.3 plenary and subgroup sessions from 08:30 to 17:10] Following a meeting of the drafting committee, members were invited to review a new draft of the resolutions. The meeting adjourned at 17:10. ........................................................................... Friday The meeting resumed at 08:30. Visitor Srinath Vadlamani was introduced. The latest draft of the resolutions was discussed and minor improvements suggested. 7. Consider the Fortran defect reports (interpretations) in J3/16-006. This agenda item was not pursued at this meeting. 8. WG5 Business and Strategic Plans 8.1 Goals for 2016-2019 A new draft of the Strategic Plan (N2106) was discussed and minor changes agreed. 9. Closing Business 9.1 Future meetings Future meetings had been considered during the discussions on resolutions. 9.2 Any other business None was raised. 10. Adoption of Resolutions [N2108] Resolutions B1, B2 and B7 to B9 were approved by unanimous acclaim. Resolutions B3 to B6 were approved by unanimous consent. 11. Adjournment The WG5 meeting adjourned at 09:30 on Friday, June 10th, 2016 and continued in PL22.3 mode until 14:05.