I recently upgraded to Ubuntu 21.10 (beta) which comes with LLVM 13.0 but the flang (Fortran compiler) package is not available. Fedora 35 (beta) which also comes with the same version of LLVM contains it. Why is it missing from Ubuntu? Should I use the LLVM apt repositories instead?
Hello, there is no currently any flang in Ubuntu, was dropped with llvm-7 and not yet introduced.
There are plans to make it build again on Debain side, but patches are welcome 
Please join irc channel at OFTC/#debian-llvm if you want to ask about the development