[flang] [llvm] [flang][OpenMP]Add support for OpenMP ERROR directive (PR #119582)

[Krzysztof Parzyszek via llvm-commits]

https://github.com/kparzysz approved this pull request.

Looks good!  Could you add checks for `-fdebug-dump-parse-tree-no-sema` as well to your testcase?

https://github.com/llvm/llvm-project/pull/119582