Flang (also known as "Classic Flang") is an out-of-tree Fortran compiler targeting LLVM. It is an open-sourced version of pgfortran, a commercial Fortran compiler from PGI/NVIDIA. It is different from the new Flang (formerly known as "F18"; see https://flang.llvm.org/), which has been part of the LLVM project since 2020, although both are developed by the same community. It is also unrelated to ot