Hello,
I couldn't reproduce this on a Westmere. Are you sure you're testing a clean compilation? Can you bisect the kernel?
I don't do a make clean normally, but I will do it this time when bisecting, also I only use shallow clones so it will also take some time pulling. Also to note, The arch I am using is Haswell, I am not sure if that should make any difference though.
What would be the difference in CONFIG_* fragments that you both have enabled?
Here is my config file: https://pastebin.com/fCNV2z8c
Thanks,