{"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"//"}]}
                //   zero-field aggregates.
                // - variant.fields.count() == 0: works fine because `ImmTy::offset` has a special case for
                // - variant.abi.is_uninhabited(): triggers UB in `read_discriminant` so we never get here.