error[E0515]: cannot return reference to temporary value
  --> $DIR/issue-17718-constants-not-static.rs:5:30
   |
LL | fn foo() -> &'static usize { &id(FOO) }
   |                              ^-------
   |                              ||
   |                              |temporary value created here
   |                              returns a reference to data owned by the current function

error: aborting due to previous error

For more information about this error, try `rustc --explain E0515`.