I notice there is [extension/opencoarrys.f90](https://github.com/sourceryinstitute/opencoarrays/blob/master/src/extensions/opencoarrays.f90)
``` fortran
! Proposed Fortran 2015 co_sum parallel coll…
```
The 1.2 UPC Spec does not currently specify atomic memory operations, however,
UPC AMO extensions have been implemented by LBL, MTU, and some vendors. All
the implementations vary, so I have li…