syntax_data: {"ast_node_type":"variable","tokens":[{"end":69,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let (lhs_size, _) = ty.int_size_and_signed(self.tcx);
context_before:                 // so this cast can never make us miss an overflow.
context_after:                 assert!(lhs_size.bits() <= 128);