Rollup merge of #30154 - salty-horse:guessing_panic, r=steveklabnik
Rollup merge of #30154 - salty-horse:guessing_panic, r=steveklabnik

The text mentions ```return```, but what's actually happening is a ```panic!```.

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