syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"*variants[FIRST_VARIANT].raw.last_mut().unwrap()"}]}
source_snippet:                 *variants[FIRST_VARIANT].raw.last_mut().unwrap() = tail_replacement;
context_before:                 let tail_replacement = cx.layout_of(Ty::new_slice(tcx, tcx.types.u8)).unwrap();