tests/ui/attributes/issue-100631.rs

// issue #100631, make sure `TyCtxt::get_attr` only called by case that compiler
// can reasonably deal with multiple attributes.
// `repr` will use `TyCtxt::get_attrs` since it's `DuplicatesOk`.
#[repr(C)] //~ ERROR: unsupported representation for zero-variant enum [E0084]
#[repr(C)]
enum Foo {}

fn main() {}