[Bug fortran/69090] New: Allocatable arrays mishandled in 'omp declare target'

[amonakov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69090

            Bug ID: 69090
           Summary: Allocatable arrays mishandled in 'omp declare target'
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: openmp
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: amonakov at gcc dot gnu.org
                CC: jakub at gcc dot gnu.org
  Target Milestone: ---

Compiling and running the following testcase with non-shared-memory accelerator
segfaults in the target region, because only pointed-to data of the allocatable
array is copied, but not the array structure (.data, .offset fields) itself. 
>From my reading of the OpenMP spec, allocatable arrays are not explicitely
allowed in the 'declare target' directive, so the code is ill-formed. However,
no diagnostic is issued, and generally I don't know what GCC intends to do
here.

(notably, this test works fine without the 'declare target' directive)

      DOUBLE PRECISION, ALLOCATABLE, DIMENSION(:), SAVE :: arr

!$omp declare target(arr)

      ALLOCATE(arr(16384))

!$omp target
       arr(2) = 1
!$omp end target

      END PROGRAM