Just bringing this topic back since we now have OpenACC 3.0 parsing and semantic checking landed in Flang. The idea of the OpenACC dialect remains the same.
It can live in the Flang directory but would work only with the FIR dialect.
If it is part of the core MLIR then we plan to make it work with the core dialects as well. This will also allow some interaction/sharing between the OpenMP and OpenACC dialects. Any comments on this?