// Copyright 2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #![deny(unused_variables)] fn f(_: i32) {} fn main() { let mut v = 0; f(v); v = match 0 { a => 0 }; //~ ERROR: unused variable: `a` f(v); }