amdflang: firstprivate(p1) on one target and map(to: p1) on a later target rejected as if on the same construct

Legality: independently confirmed. 2 independent readings find the program legal and the result required. How this is checked

Affected variants

Compiler	MI300A 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 24.3.0	not supported	not supported	not supported	not supported	not supported	n/a	n/a
CCE 19.0.0	correct	correct	correct	unknown not run	unknown not run	n/a	n/a
CCE 20.0.2	correct	correct	correct	unknown not run	unknown not run	n/a	n/a
CCE 21.0.3	correct	correct	correct	unknown not run	unknown not run	n/a	n/a
CCE 21.0.4	correct	correct	correct	unknown not run	unknown not run	n/a	n/a
NVHPC 25.11	n/a	n/a	n/a	n/a	n/a	correct	correct
NVHPC 26.9	n/a	n/a	n/a	n/a	n/a	correct	correct
GCC 16.2.0	correct	correct	correct	correct	correct	correct	n/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

Result	Compiler and GPU	Message
not supported	AFAR 24.3.0, MI300A unified AFAR 24.3.0, MI300A copy AFAR 24.3.0, MI250X AFAR 24.3.0, MI300X AFAR 24.3.0, MI350X	show error: Semantic errors in afar-flang-firstprivate-map-two-targets.f90 afar-flang-firstprivate-map-two-targets.f90:5:29: error: Variable 'p1' may not appear on both MAP and FIRSTPRIVATE clauses on a TARGET construct !$omp target firstprivate(p1) map(from: a) ^^

Result

Compiler and GPU

Message

not supported

AFAR 24.3.0, MI300A unified
AFAR 24.3.0, MI300A copy
AFAR 24.3.0, MI250X
AFAR 24.3.0, MI300X
AFAR 24.3.0, MI350X

show

error: Semantic errors in afar-flang-firstprivate-map-two-targets.f90
afar-flang-firstprivate-map-two-targets.f90:5:29: error: Variable 'p1' may not appear on both MAP and FIRSTPRIVATE clauses on a TARGET construct
    !$omp target firstprivate(p1) map(from: a)
                              ^^

Reproduce

AFAR 24.3.0, MI300A unified

$AFAR/bin/amdflang -fopenmp --offload-arch=gfx942 -O2 repro.f90 -o repro
HSA_XNACK=1 OMP_TARGET_OFFLOAD=mandatory ./repro

CCE 19.0.0, MI300A unified (runs correctly)

module load cce/19.0.0 craype-accel-amd-gfx942 rocm/6.4.3
module unload cray-mpich
ftn -fopenmp -O2 repro.f90 -o repro
HSA_XNACK=1 OMP_TARGET_OFFLOAD=mandatory ./repro

Program (27 lines)

program p
  implicit none
  integer :: a(10), i, p1
  p1 = 3
  !$omp target firstprivate(p1) map(from: a)
    do i = 1, 10
      a(i) = p1
    end do
  !$omp end target
  !$omp target map(to: p1) map(tofrom: a)
    do i = 1, 10
      a(i) = a(i) + p1
    end do
  !$omp end target
  print *, 'a(3) =', a(3)
end program p
! spec (requirement): The data environment of each target task is created from the data-sharing and data-mapping
!   clauses on that one target construct, so clauses on different target constructs do not interact.
! "The data environment of the target task is created according to the data-sharing and data-mapping attribute clauses
!   on the target construct" (5.2 §13.8 p.284 l.19-21)
! spec (requirement): A firstprivate list item on a target construct is initialized from the original list item that
!   exists before that construct.
! "In addition, the new list item is initialized from the original list item that exists before the construct." (5.2
!   §5.4.4 p.112 l.11-12)
! spec (this program): p1 is firstprivate on the first target construct and appears in map(to:) only on the second,
!   separate target construct, so no list item has two attributes on one construct; amdflang rejects the second target
!   as if both clauses were on the same construct.

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

a(3) = 6

Observed where it behaves incorrectly

error: Semantic errors in afar-flang-firstprivate-map-two-targets.f90
afar-flang-firstprivate-map-two-targets.f90:5:29: error: Variable 'p1' may not appear on both MAP and FIRSTPRIVATE clauses on a TARGET construct
    !$omp target firstprivate(p1) map(from: a)
                              ^^

What the specification requires

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

OpenMP 5.2 §13.8 p.284 l.19-21

The data environment of the target task is created according to the data-sharing and data-mapping attribute clauses on the target construct

OpenMP 5.2 §5.4.4 p.112 l.11-12

In addition, the new list item is initialized from the original list item that exists before the construct.

Evidence

Same compiler, one change

map(to: p1) instead of firstprivate(p1) on the first target: AFAR 24.3.0: correct; CCE 19.0.0: correct; CCE 20.0.2: correct; CCE 21.0.3: correct; CCE 21.0.4: correct

Control program

program p
  implicit none
  integer :: a(10), i, p1
  p1 = 3
  !$omp target map(to: p1) map(from: a)
    do i = 1, 10
      a(i) = p1
    end do
  !$omp end target
  !$omp target map(to: p1) map(tofrom: a)
    do i = 1, 10
      a(i) = a(i) + p1
    end do
  !$omp end target
  print *, 'a(3) =', a(3)
end program p

Other compilers run it correctly

CCE 19.0.0, CCE 20.0.2, CCE 21.0.3, CCE 21.0.4, NVHPC 25.11, NVHPC 26.9, GCC 16.2.0