The FAQ says: It is sometimes asked if there is any way to get a copy of exactly the code used to build a snapshot. The answer is no.
For this to change, it would be sufficient if the output of find src XF4 -path '*/CVS/Entries' -exec perl -ne \ 'm:^(/[^/]*/[^/]*): && print substr($ARGV,0,-12),"$1\n"' '{}' ';' (or equivalent information) accompanies the snapshot. That would not work. Often snapshots contain uncommited diffs as well. Another issue is that I will do cvs updates on the source trees while doing builds on all the architectures in parallel. No kidding. And yes, I am careful, and yes, even I sometimes make a few mistakes in this process. What you ask for will never happen. I've got more than enough to do.