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Observed issues › gcc/gcc-omp60-unimplemented-rejected

Appears not to supportRefused at compile time · Fortran · OpenMP · Open

OpenMP 6.0 features that GCC 16.2 lists as not implemented are rejected (Fortran)

Legality: not independently confirmed. no independent review yet How this is checked

Same issue as gcc/gcc-c-omp60-unimplemented-rejected; this program is another reproducer of it.

GCC 16.2 rejects OpenMP 6.0 forms that its implementation status table lists as not implemented: directive-name modifiers on clauses, the induction, local, replayable and transparent clauses, num_threads(strict:), variable categories on default, defaultmap(self/storage), map(self:/storage:/ref_*), firstprivate(saved:), reduction(original:), arguments on requires clauses and nowait, nogroup on target_data, and the underscore spellings of multi-word directives. Most stop with a syntax error; declare target local stops with "Sorry, ... not implemented", nogroup with "'nogroup' is not valid for '#pragma omp target data'", and the ignored declare_mapper leaves its mapper "not found". GCC 16.2 claims OpenMP 5.2 (_OPENMP 202111) and parts of 6.0.

Affected variants

CompilerMI300A gfx942
unified memory (XNACK 1)
MI300A gfx942
copy (XNACK 0)
MI250X gfx90a
copy (XNACK 0)
MI300X gfx942
copy (XNACK 0)
MI350X gfx950
copy (XNACK 0)
A100 sm_80
separate memory
A100 sm_80
managed memory
AFAR 24.3.0fails another wayfails another wayunknown
not run
fails another wayfails another wayn/an/a
CCE 19.0.0fails another wayfails another wayunknown
not run
unknown
not run
unknown
not run
n/an/a
CCE 20.0.2fails another wayfails another wayunknown
not run
unknown
not run
unknown
not run
n/an/a
CCE 21.0.3fails another wayfails another wayunknown
not run
unknown
not run
unknown
not run
n/an/a
CCE 21.0.4fails another wayfails another wayunknown
not run
unknown
not run
unknown
not run
n/an/a
NVHPC 25.11n/an/an/an/an/afails another wayfails another way
NVHPC 26.9n/an/an/an/an/afails another wayfails another way
GCC 16.2.0not supportednot supportednot supportednot supportednot supportednot supportedn/a

"behaves incorrectly" / "not supported": this issue, confirmed in up to four environments (another build directory, another node, a repeat). "fails another way": a different failure, not counted as this issue. "unknown": not run there, or the runs disagree.

Messages

ResultCompiler and GPUMessage
not supportedGCC 16.2.0, MI300A unified
GCC 16.2.0, MI300A copy
GCC 16.2.0, MI250X
GCC 16.2.0, MI300X
GCC 16.2.0, MI350X
GCC 16.2.0, A100 separate
show
site-gcc--gcc-omp60-unimplemented-rejected.f90:91:50:
   91 |     !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
      |                                                  1
Error: Failed to match clause at (1)
site-gcc--gcc-omp60-unimplemented-rejected.f90:96:25:
   96 |     !$omp end parallel do
      |                         1
Error: Unexpected !$OMP END PARALLEL DO statement at (1)
fails another wayAFAR 24.3.0, MI300A unified
AFAR 24.3.0, MI300A copy
AFAR 24.3.0, MI300X
AFAR 24.3.0, MI350X
show
error: Could not parse site-gcc--gcc-omp60-unimplemented-rejected.f90
site-gcc--gcc-omp60-unimplemented-rejected.f90:91:67: error: expected ':'
      !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
                                                                    ^
site-gcc--gcc-omp60-unimplemented-rejected.f90:91:50: in the context: pointer assignment statement
      !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
                                                   ^
site-gcc--gcc-omp60-unimplemented-rejected.f90:89:3: in the context: OpenMP construct
fails another wayCCE 19.0.0, MI300A unified
CCE 19.0.0, MI300A copy
show
Warning:
 Headers and libraries from cray-libsci/25.03.0 will be ignored because depends on PE_MPICH which is unavailable..
    !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
                                                 ^                        
ftn-1519 ftn: ERROR GEN_PROG, File = site-gcc--gcc-omp60-unimplemented-rejected.f90, Line = 91, Column = 50 
  Invalid clause "INDUCTION" for directive !$OMP PARALLEL DO.  Valid clauses: IF, PRIVATE, SHARED, FIRSTPRIVATE, DEFAULT, COPYIN, REDUCTION, LASTPRIVATE, ORDERED, SCHEDULE, SCHEDULE, NUM_THREADS, COLL
Cray Fortran : 112 source lines
Cray Fortran : 1 errors, 0 warnings, 0 other messages, 0 ansi
fails another wayCCE 20.0.2, MI300A unified
CCE 20.0.2, MI300A copy
show
Warning:
 Headers and libraries from cray-libsci/25.09.0 will be ignored because depends on PE_MPICH which is unavailable..
    !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
                                                 ^                        
ftn-1519 ftn: ERROR GEN_PROG, File = site-gcc--gcc-omp60-unimplemented-rejected.f90, Line = 91, Column = 50 
  Invalid clause "INDUCTION" for directive !$OMP PARALLEL DO.  Valid clauses: IF, PRIVATE, SHARED, FIRSTPRIVATE, DEFAULT, COPYIN, REDUCTION, LASTPRIVATE, ORDERED, SCHEDULE, SCHEDULE, NUM_THREADS, COLL
Cray Fortran : 112 source lines
Cray Fortran : 1 errors, 0 warnings, 0 other messages, 0 ansi
fails another wayCCE 21.0.3, MI300A unified
CCE 21.0.3, MI300A copy
CCE 21.0.4, MI300A unified
CCE 21.0.4, MI300A copy
show
Warning:
 Headers and libraries from cray-libsci/26.03.0 will be ignored because depends on PE_MPICH which is unavailable..
    !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
                                                 ^                        
ftn-1519 ftn: ERROR GEN_PROG, File = site-gcc--gcc-omp60-unimplemented-rejected.f90, Line = 91, Column = 50 
  Invalid clause "INDUCTION" for directive !$OMP PARALLEL DO.  Valid clauses: IF, PRIVATE, SHARED, FIRSTPRIVATE, DEFAULT, COPYIN, REDUCTION, LASTPRIVATE, ORDERED, SCHEDULE, SCHEDULE, NUM_THREADS, COLL
Cray Fortran : 112 source lines
Cray Fortran : 1 errors, 0 warnings, 0 other messages, 0 ansi
fails another wayNVHPC 25.11, A100 separate
NVHPC 25.11, A100 managed
NVHPC 26.9, A100 separate
NVHPC 26.9, A100 managed
show
NVFORTRAN-S-0034-Syntax error at or near identifier induction (site-gcc--gcc-omp60-unimplemented-rejected.f90: 91)
  0 inform,   0 warnings,   1 severes, 0 fatal for gen_prog

Reproduce

GCC 16.2.0, MI300A unified

export LD_LIBRARY_PATH=$GCC_16_2/lib64:/opt/rocm-7.2.1/lib
$GCC_16_2/bin/gfortran -fopenmp -foffload=amdgcn-amdhsa -foffload-options=amdgcn-amdhsa=-march=gfx942 -O2 repro.f90 -o repro
HSA_XNACK=1 OMP_TARGET_OFFLOAD=mandatory ./repro

GCC 16.2.0, A100 separate

export PATH=/usr/local/cuda/bin:$PATH
export LD_LIBRARY_PATH=$GCC_16_2/lib64
$GCC_16_2/bin/gfortran -fopenmp -foffload=nvptx-none -foffload-options=nvptx-none=-march=sm_80 -foffload-options=nvptx-none=-latomic -O2 repro.f90 -o repro
OMP_TARGET_OFFLOAD=mandatory ./repro
Program (101 lines)
! # Finding (GCC 16.2): OpenMP 6.0 forms GCC documents as not implemented are rejected (Fortran); the reproducer is the catalog
!   program omp60-clause-induction
!
! - toolchains: gcc_g90 (GCC 16.2.0, AMD Instinct MI250X gfx90a, Tioga) and gcc_sm80 (GCC 16.2.0,
!   NVIDIA A100 sm_80, wingtip); separate memory only; -O2; OMP_TARGET_OFFLOAD=mandatory
! - build: gfortran -fopenmp -foffload=amdgcn-amdhsa -foffload-options=amdgcn-amdhsa=-march=gfx90a -O2 (gcc_g90);
!   -foffload=nvptx-none -foffload-options=nvptx-none=-march=sm_80 -foffload-options=nvptx-none=-latomic -O2 (gcc_sm80)
! - failure: rejected
! - observed: a compile-time error for every program of the list (the first: `Error: Failed to match clause at (1)`; declare target
!   local: `Sorry, OMP DECLARE TARGET with LOCAL clause not implemented`); the same on both GPUs.
! - expected: compiles; `RESULT ran_on_host=0 check=pass`
! - GCC 16.2 documentation (libgomp.texi of the GCC 16.2.0 release tarball, "OpenMP Implementation Status", OpenMP 6.0 table) lists
!   each of these as not implemented (N): "directive-name-modifier accepted in all clauses", "Support for inductions", "local clause
!   to declare_target directive", "New taskgraph construct including saved modifier and replayable clause", "New transparent clause
!   for multi-generational task-dependence graphs", "strict modifier keyword to num_threads", "default clause on the target
!   directive and accepting variable categories", "New storage map-type modifier", "self modifier to map and self as defaultmap
!   argument", "ref modifier to the map clause", "Reduction over private variables with reduction clause" (the original modifier),
!   "Boolean argument to nowait and nogroup may be non constant", "target_data as composite construct" (nogroup on target_data),
!   "All inarguable clauses take now an optional Boolean argument" (the requires clauses' argument), "For Fortran, the automap
!   modifier to the enter clause", "workdistribute directive for Fortran" and "Multi-word directives now use underscore by default"
!   (declare_simd, declare_mapper, target_loop). The two 6.0 forms no row covers (requires device_safesync, defaultmap(private)) are
!   a finding of their own (gcc-c-omp60-undocumented-rejected).
! - spec: the induction clause (6.0 §7.6.13 p.257), the directive-name-modifier (6.0 §5.4 p.173), the replayable clause (6.0 §14.6
!   p.440), the transparent clause (6.0 §17.9.6 p.510).
! - gate and confirmer: 184 cells (92 gcc_g90, 92 gcc_sm80), each confirmed in the gate's four environments (a-d;
!   results/gcc/gate-tioga/ and gate-wingtip/ verdicts.jsonl); confirmer verdicts (results/gcc/confirm/batch.gcc_*.jsonl):
!   unsupported (R11a-newer-form-unclaimed) 184
! - catalog programs (92): omp60-clause-aligned-directive_name, omp60-clause-allocate-directive_name,
!   omp60-clause-atomic_default_mem_order-directive_name, omp60-clause-bind-directive_name, omp60-clause-collapse-directive_name,
!   omp60-clause-default-aggregate, omp60-clause-default-all, omp60-clause-default-allocatable, omp60-clause-default-directive_name,
!   omp60-clause-default-pointer, omp60-clause-default-scalar, omp60-clause-defaultmap-directive_name, omp60-clause-defaultmap-self,
!   omp60-clause-defaultmap-storage, omp60-clause-depend-directive_name, omp60-clause-device-directive_name,
!   omp60-clause-device_type-directive_name, omp60-clause-dist_schedule-directive_name,
!   omp60-clause-dynamic_allocators-directive_name, omp60-clause-dynamic_allocators-required, omp60-clause-enter-automap,
!   omp60-clause-enter-directive_name, omp60-clause-firstprivate-directive_name, omp60-clause-firstprivate-saved,
!   omp60-clause-from-directive_name, omp60-clause-has_device_addr-directive_name, omp60-clause-in_reduction-directive_name,
!   omp60-clause-indirect-directive_name, omp60-clause-induction, omp60-clause-induction-directive_name,
!   omp60-clause-induction-plus, omp60-clause-induction-relaxed, omp60-clause-induction-step, omp60-clause-induction-strict,
!   omp60-clause-induction-times, omp60-clause-is_device_ptr-directive_name, omp60-clause-lastprivate-directive_name,
!   omp60-clause-linear-directive_name, omp60-clause-linear-ref, omp60-clause-linear-uval, omp60-clause-link-directive_name,
!   omp60-clause-local, omp60-clause-local-directive_name, omp60-clause-map-directive_name, omp60-clause-map-ref_ptee,
!   omp60-clause-map-ref_ptr, omp60-clause-map-ref_ptr_ptee, omp60-clause-map-self, omp60-clause-map-storage,
!   omp60-clause-message-directive_name, omp60-clause-nogroup, omp60-clause-nogroup-directive_name,
!   omp60-clause-nogroup-do_not_synchronize, omp60-clause-nontemporal-directive_name, omp60-clause-nowait-directive_name,
!   omp60-clause-nowait-do_not_synchronize, omp60-clause-num_teams-directive_name, omp60-clause-num_threads-directive_name,
!   omp60-clause-num_threads-strict, omp60-clause-order-directive_name, omp60-clause-ordered-directive_name,
!   omp60-clause-private-directive_name, omp60-clause-proc_bind-directive_name, omp60-clause-reduction-directive_name,
!   omp60-clause-reduction-original, omp60-clause-replayable, omp60-clause-replayable-directive_name,
!   omp60-clause-replayable-replayable_expression, omp60-clause-reverse_offload-directive_name,
!   omp60-clause-reverse_offload-required, omp60-clause-safelen-directive_name, omp60-clause-schedule-directive_name,
!   omp60-clause-self_maps-directive_name, omp60-clause-self_maps-required, omp60-clause-severity-directive_name,
!   omp60-clause-shared-directive_name, omp60-clause-simdlen-directive_name, omp60-clause-thread_limit-directive_name,
!   omp60-clause-to-directive_name, omp60-clause-transparent, omp60-clause-transparent-directive_name,
!   omp60-clause-transparent-impex_type, omp60-clause-unified_address-directive_name, omp60-clause-unified_address-required,
!   omp60-clause-unified_shared_memory-directive_name, omp60-clause-unified_shared_memory-required,
!   omp60-clause-use_device_addr-directive_name, omp60-clause-use_device_ptr-directive_name,
!   omp60-clause-uses_allocators-directive_name, omp60-directive-target_loop, omp60-directive-target_teams_workdistribute,
!   omp60-directive-teams_workdistribute
! - legality: the catalog programs are legal by construction (offload.engine.gen, c_gen and acc_gen
!   check every program against the catalog rules and the offload scope as it is built; no
!   compiler). GCC is a compiler under test only: never a legality witness, here or for another
!   family's case (catalog/machines.yaml under_test_only).
! Generated by compliance.gen (OpenMP 6.0, free-form Fortran). Do not edit.
! id: omp60-clause-induction
! primary atom: omp.clause.induction
! legal: yes
! observable: yes
! ran_on_host: inside the target region of interest
! evidence: construct
! needs: none
! std: f2008
program gen_prog
  use omp_lib, only: omp_is_initial_device
  implicit none
  integer, parameter :: n = 64
  integer, allocatable, target :: a(:), b(:)
  integer :: ref(n)
  integer :: i, host_flag
  logical :: ok
  integer :: x
  allocate(a(n), b(n))
  do i = 1, n
    a(i) = i
    b(i) = 0
    ref(i) = 2*i + 1
  end do
  host_flag = 1
  x = 3
  !$omp target map(to: a) map(from: b) map(tofrom: x) map(tofrom: host_flag)
    host_flag = merge(1, 0, omp_is_initial_device())
    !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
      do i = 1, n
        b(i) = 2*a(i) + 1 + (x - (i + 2))
        x = x + 1
      end do
    !$omp end parallel do
  !$omp end target
  ok = all(b == ref) .and. (x == n + 3)
  print '(a,i0,a,a)', 'RESULT ran_on_host=', host_flag, ' check=', merge('pass', 'fail', ok)
  deallocate(a, b)
end program gen_prog

Source in the repository

Something to add? Dispute its legality · Report it fixed in a newer release · Report a mistake on this page

Expected and observed

Expected

check=pass

Observed where it behaves incorrectly

site-gcc--gcc-omp60-unimplemented-rejected.f90:91:50:
   91 |     !$omp parallel do default(none) shared(a, b) induction(step(1), +: x)
      |                                                  1
Error: Failed to match clause at (1)
site-gcc--gcc-omp60-unimplemented-rejected.f90:96:25:
   96 |     !$omp end parallel do
      |                         1
Error: Unexpected !$OMP END PARALLEL DO statement at (1)

What the specification requires

The specification text this program relies on and the compiler is expected to support.

OpenMP 6.0 §7.6.13 p.257

OpenMP 6.0 §5.4 p.173

OpenMP 6.0 §14.6 p.440

OpenMP 6.0 §17.9.6 p.510