corp.generalmills.com has no CNAME records.
Question and response
Question
dig corp.generalmills.com. NS
Answer
The response has no answer records.
Authority
generalmills.com. 479 SOA mgoextdns1.genmills.com. dom\.admin.genmills.com. 15893 900 600 2419200 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0