error[E0308]: `if` and `else` have incompatible types
  --> $DIR/region-invariant-static-error-reporting.rs:21:9
   |
LL |       let bad = if x.is_some() {
   |  _______________-
LL | |         x.unwrap()
   | |         ---------- expected because of this
LL | |     } else {
LL | |         mk_static()
   | |         ^^^^^^^^^^^ lifetime mismatch
LL | |     };
   | |_____- `if` and `else` have incompatible types
   |
   = note: expected struct `Invariant<'a>`
              found struct `Invariant<'static>`
note: the lifetime `'a` as defined here...
  --> $DIR/region-invariant-static-error-reporting.rs:17:10
   |
LL | fn unify<'a>(x: Option<Invariant<'a>>, f: fn(Invariant<'a>)) {
   |          ^^
   = note: ...does not necessarily outlive the static lifetime

error: aborting due to previous error

For more information about this error, try `rustc --explain E0308`.