[flang] [llvm] [flang][runtime] Replace recursion with iterative work queue (PR #137727)

[Valentin Clement バレンタイン クレメン via llvm-commits]

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

I run some tests and the recursion problem seems to be addressed as expected. 

https://github.com/llvm/llvm-project/pull/137727