Function rustc_incremental::in_incr_comp_dir

pub fn in_incr_comp_dir(
    incr_comp_session_dir: &Path,
    file_name: &str
) -> PathBuf

Returns the path for a given filename within the incremental compilation directory, not necessarily from the current session.

To ensure the file is part of the current session, use in_incr_comp_dir_sess.