syntax_data: {"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                 // With metadata. Must be unsized and not on the stack.
context_before:             PassMode::Indirect { meta_attrs: Some(_), on_stack, .. } => {
context_after:                 assert!(arg.layout.is_unsized() && !on_stack);