[Bug fortran/114283] New: [OpenMP] Dummy procedures/proc pointers and 'defaultmap', 'default', 'firstprivate' etc.

[Bug fortran/114283] New: [OpenMP] Dummy procedures/proc pointers and 'defaultmap', 'default', 'firstprivate' etc.

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114283

            Bug ID: 114283
           Summary: [OpenMP] Dummy procedures/proc pointers and
                    'defaultmap', 'default', 'firstprivate' etc.
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: openmp
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
  Target Milestone: ---

See also OpenMP specification Issue #3823 [and slightly related PR 114282].

There are two cases:

(A) Dummy procedures

IMHO those aren't variables and gfortran also rejects them when used in
firstprivate, map, shared etc. ("Object 'f1' is not a variable").

However, gfortran does complain with 'default(none)':
   Error: 'f1' not specified in enclosing 'target'

Note: 'default(none)' does not diagnose it.
EXPECTED: There is no diagnosis for 'defaultmap(none)'.


(B) Procedure pointers

Here it is unclear whether it should be regarded as variable or not; gfortran
treats those as variables.

Depends on OpenMP specification Issue #3823.

It seems as if handling it as variable, but using 'firstprivate' as default for
implicit mapping makes most sense. – But also treating it as non-variable would
make sense.

[Bug fortran/114283] [OpenMP] Dummy procedures/proc pointers and 'defaultmap', 'default', 'firstprivate' etc.

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114283

--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tobias Burnus <burnus@gcc.gnu.org>:

https://gcc.gnu.org/g:c5037fcee2de438774466e78e46e6ab4df72a7fe

commit r14-9446-gc5037fcee2de438774466e78e46e6ab4df72a7fe
Author: Tobias Burnus <tburnus@baylibre.com>
Date:   Wed Mar 13 09:35:28 2024 +0100

    OpenMP/Fortran: Fix defaultmap(none) issue with dummy procedures [PR114283]

    Dummy procedures look similar to variables but aren't - neither in Fortran
    nor in OpenMP. As the middle end sees PARM_DECLs, mark them as
predetermined
    firstprivate for mapping (as already done in
gfc_omp_predetermined_sharing).

    This does not address the isses related to procedure pointers, which are
    still discussed on spec level [see PR].

            PR fortran/114283

    gcc/fortran/ChangeLog:

            * trans-openmp.cc (gfc_omp_predetermined_mapping): Map dummy
            procedures as firstprivate.

    libgomp/ChangeLog:

            * testsuite/libgomp.fortran/declare-target-indirect-4.f90: New
test.