Hartmut Kaiser

@Johan511 Sure, that works. I almost think it might be easier to start over from master and step by step reapply necessary changes, i.e. add module support to the build...

> @hkaiser do you suggest I fork master and start working on it? where do you think I should start? Yes, I'd start with creating a new branch and reapplying...

> Sorry for the delay, I have gone through the master branch and tried to figure out to what extent modules have been implemented. There seems to be a cmake...

> Hi @gonidelis, thank you for the resource. One thing I would like to point out is that they suggest using the FILE_SET option which seem to be introduced only...

BTW, in addition to my [comment above](https://github.com/STEllAR-GROUP/hpx/issues/6014#issuecomment-1397285555). The HPX Modules `core/preprocessor` and `core/config_registry` are special, as those are the only ones that do not depend on the HPX module `config/config`...

@Johan511 you might want to watch this video: https://www.youtube.com/watch?v=5X803cXe02Y. There the speaker explains how to enable experimental support for C++ modules (amongst other things). Essentially this: 

> I have managed to get everything setup, and updated/added some cmake files to add c++20 module. To initially test it out, I am trying to generate a module of...

@akcube thanks again for your work on this. I have rebased your branch and have done some cleanup to match recent changes. Please have a look and comment. I hope...

bors merge

> @hkaiser Do you know if we fixed that or is it still open? We have not tried recently. @SAtacker: would you be able to check?