Auto merge of #31940 - teoryn:patch-2, r=steveklabnik
Auto merge of #31940 - teoryn:patch-2, r=steveklabnik

See http://www.ietf.org/rfc/rfc2119.txt

GBGamer/rust,graydon/rust,graydon/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,graydon/rust,graydon/rust,GBGamer/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,GBGamer/rust,aidancully/rust,aidancully/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,GBGamer/rust