{"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"//"}]}
            // the check in `visit_value`.
            // Unsized unions are currently not a thing, but let's keep this code consistent with
            let zst = self.ecx.size_and_align_of_val(val)?.is_some_and(|(s, _a)| s.bytes() == 0);