ISO/IEC JTC1/SC22/WG5 N971 S L A C M E M O R A N D U M February 23, 1994 ---------------------------- To: Interested FORTRAN users From: L. Moss Subject: Trip Report on X3J3 meeting, 7 - 11 Feb, 1994 ----------------------------------------------------------------- Note: This is a personal report of these meetings and in no sense does it constitute an official record. X3J3 met in Palmdale, California from 7 through 11 February 1994. The US TAG (Technical Advisory Group) for Fortran (which consists of US members of X3J3) held brief sessions on Tuesday and Thursday afternoons (8 and 10 February) which I will report on separately. The principal goals for this meeting were to: * continue work on the preliminary list of Fortran 95 requirements contained in Resolution B9 from last summer's WG5 meeting; and, * continue processing Fortran 90 defect reports. B9 PROPOSALS ------------ Substantial progress was made in processing the various items contained in resolution 9 from the WG5 meeting in Berchtesgaden, Germany last July. At the end of the meeting the status of these items was (in the following, "009" is shorthand for X3J3/94-009, the standing document which collects approved proposals for new or changed features of Fortran 95): A Items WG5 definitely intends to be in Fortran 95: 1. Corrigenda and modest editorial improvements -------------------------------------------- Many of these have already been incorporated into 94-007, the standing document that will become the draft Fortran 95 standard. 2. FORALL statement ---------------- Preliminary 009 specification and rationale (94-096, 94-097) approved by unanimous consent. 3. FORALL construct ---------------- Preliminary 009 specification and rationale (94-096, 94-097) approved by unanimous consent. 4. PURE prefix on functions ------------------------ Preliminary 009 specification and rationale (94-098, 94-097) approved by unanimous consent. 5. Add DIM to MAXLOC, MINLOC ------------------------- 009 specification (94-037) approved by a vote of 11*-6. B Desirable features for Fortran 95: 1. Object initialization --------------------- Preliminary 009 specification (94-031r2) approved by unanimous consent: permits a new intrinsic function, NULL, to initialize pointers in structure constructors and initializations; also permits default initialization of components in derived type definitions, including NULL for pointer components. A related new requirement was drafted by the /oof subgroup and received favorable straw votes. The idea was to make structure constructors more like procedures and to permit them to be overloaded by the user. 2. Remove conflicts with IEEE arithmetic ------------------------------------- A draft proposal was due at this meeting to remove any apparent conflicts between IEEE 754/854 and Fortran. This proposal was not ready, but should be available for the next meeting. 3. Allocatable components in structures ------------------------------------ A 009 specification is due at the next meeting. 4. Miscellaneous 1 MINIMAL AND EXACT FIELD WIDTH EDITING: 009 ------------------------------------- specification (94-022r1) for minimal field width editing approved by a vote of 17*-2. 2 SPECIFICATION OF FURTHER OBSOLESCENT FEATURES: --------------------------------------------- A proposal (Proposal 1 of 94-080r1) to keep a complete description of deleted features in an annex of the standard (like Hollerith in the Fortran 77 standard) was passed by a vote of 17*-1. With this proviso, proposal 5.1 of 94-047r1 to delete the following obsolescent features was passed by a vote of 16*-3: Real and double precision DO variables Branching to END IF PAUSE ASSIGN, assigned GO TO, assigned formats cH edit descriptor A proposal to add the following items to the obsolescent list was also approved, 18*-1: Computed GO TO Statement functions DATA statements amongst executables Assumed length character functions Fixed form source Assumed size arrays CHARACTER* form of CHARACTER declaration 3 COMMENTS IN NAMELIST AND LIST-DIRECTED INPUT: -------------------------------------------- 009 specification (94-021) for comments in namelist input approved, 16*-2. C Areas requiring further investigation by X3J3 so that a decision on final requirements can be made by the summer 1994 WG5 meeting: 1. CPU-time intrinsic function --------------------------- At meeting 127, the committee expressed a desire to await the results of POSIX work on CPU-time system calls in multi-processing environments. Currently awaiting recommendation from the new X3J3/osci subgroup. 2. KIND parameters for derived types --------------------------------- Tutorial presented on a draft proposal, 94-047r2. This proposal permits multiple parameters of both the KIND and NONKIND varieties (the former must be static constants and are used to determine KIND parameters of intrinsic types; the latter determine the size of arrays or CHARACTERs and may be specification expressions). It also introduces a new "operator", %%, to inquire about the parameters of objects. For example, if x is an object of derived type Matrix, and if size is a parameter of Matrix, then x%%size returns the size parameter for object x. A straw vote of 10-0-7* indicated that the committee favored this approach. A 009 specification is due at the next meeting. 3. Allow some user-defined functions in declarations ------------------------------------------------- A proposal (94-012) to add the specific new intrinsics needed in initialization expressions to support some HPF programs (i.e., NUMBER_OF_PROCESSORS, PROCESSORS_SHAPE, and ILEN) was discussed and a draft 009 specification should be presented at the next meeting. A more limited requirement, namely to permit user-defined PURE functions accessed via USE association in specification expressions, was also discussed and a draft 009 specification along these lines will also be prepared for the next meeting. 4. Support IEEE hardware --------------------- A recommendation to pursue this as a separate, IEEE/Fortran binding standard was approved by a vote of 12*-3. 5. Exception handling ------------------ A tutorial was presented and a number of straw votes were taken on this topic. A recommendation to actively pursue an exception handling requirement, but targeted at the Fortran 2000 revision cycle, was approved, 15*-1. 6. Object oriented programming --------------------------- An investigation of object-oriented issues is continuing in the /oof subgroup, particularly to help determine general directions for other B9 items (i.e., B1, B3 and C2). No additional proposals have yet emerged. 7. Derived type I/O ---------------- X3J3 previously recommended deferring this requirement to the Fortran 2000 revision cycle. FORTRAN 90 MAINTENANCE ---------------------- Processing of defect reports continued. At the beginning of the meeting there were 49 open defect items, including 11 that failed the letter ballot following the last meeting (the other 13 items on that ballot were approved and sent on to WG5) and 3 new items. At the end of meeting 128 a total of 21 items were ready for an X3J3 letter ballot, and 28 needed further work. ADMINISTRATIVE BUSINESS ----------------------- MEMBERSHIP At the beginning of this meeting X3J3 had 28 members, giving a quorum of 8 (=1+INT(Members/3)), and a majority of the membership of 15 (=1+INT(Members/2)). At the end of the meeting, one member had resigned and several (five, I think) were in jeopardy. FUTURE MEETINGS: 129th 2-6 May 1994, Lake Tahoe, CA (host: Tom Lahey). ----- 1994 WG5 Meeting ---------------- 8-12 August 1994, Edinburgh, Scotland (host: David Muxworthy). 130th 15-19 August 1994, Edinburgh, Scotland (host: Geoff ----- Millard). 131st 7-11 November 1994, Boston, MA (host: David Levine). ----- 132nd January 1995, Houston, TX (host: Jerry Wagener). ----- 1994 WG5 Meeting ---------------- 17-21 April 1995, Japan 133rd 24-29 April 1995, Maui, Hawaii (host: Brian Smith). ----- NEXT DISTRIBUTION The closing date for the next pre-meeting distribution is 28 March 1994. 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