https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108854
--- Comment #6 from davidak <gcc.gnu.org+lufm at davidak dot de> --- I tried to get the preprocessed source for the last 2 hours, but it does not end up in the build directory. Maybe Nix does some clean up at the end. I left a note in the downstream issue that they should provide you the files. The people at Intel should be more capable than me. Sorry