Add an idealistic test for optimize attribute
Add an idealistic test for optimize attribute

Alas it does not currently work, because of limitations in compiletest…

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