[flang-commits] [flang] [semantics][acc] start handling clauses that use sections and components (PR #211606)

[Eugene Epshteyn via flang-commits]

eugeneepshteyn wrote:

AI agent suggested to check the following test:
```fortran
integer :: x, i
x = 0
!$acc parallel copy(x) reduction(+:x)   ! PR: error; baseline: clean; spec: legal (its own example)
!$acc loop gang reduction(+:x)
do i = 1, 100
  x = x + 1
end do
!$acc end parallel
```
In OpenACC 3.3 spec, `!$acc parallel copy(x) reduction(+:x)` is used in an example on page 66.

https://github.com/llvm/llvm-project/pull/211606