error[E0392]: lifetime parameter `'a` is never used --> $DIR/issue-36299.rs:1:12 | LL | struct Foo<'a, A> {} | ^^ unused lifetime parameter | = help: consider removing `'a`, referring to it in a field, or using a marker such as `PhantomData` error[E0392]: type parameter `A` is never used --> $DIR/issue-36299.rs:1:16 | LL | struct Foo<'a, A> {} | ^ unused type parameter | = help: consider removing `A`, referring to it in a field, or using a marker such as `PhantomData` = help: if you intended `A` to be a const parameter, use `const A: /* Type */` instead error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0392`.