error: lifetime may not live long enough
  --> $DIR/regions-bounds.rs:9:12
   |
LL | fn a_fn1<'a,'b>(e: TupleStruct<'a>) -> TupleStruct<'b> {
   |          -- -- lifetime `'b` defined here
   |          |
   |          lifetime `'a` defined here
LL |     return e;
   |            ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
   |
   = help: consider adding the following bound: `'a: 'b`

error: lifetime may not live long enough
  --> $DIR/regions-bounds.rs:14:12
   |
LL | fn a_fn3<'a,'b>(e: Struct<'a>) -> Struct<'b> {
   |          -- -- lifetime `'b` defined here
   |          |
   |          lifetime `'a` defined here
LL |     return e;
   |            ^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a`
   |
   = help: consider adding the following bound: `'a: 'b`

error: aborting due to 2 previous errors