[flang] [llvm] [Flang][OpenMP] Generate correct present checks for implicit maps of optional allocatables (PR #138210)

[Sergio Afonso via llvm-commits]

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

Thank you Andrew, LGTM. Please wait for @jeanPerier's approval before merging, though.

https://github.com/llvm/llvm-project/pull/138210