src/test/compile-fail/liveness-dead.rs

   1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![allow(dead_code)]
  12 #![deny(unused_assignments)]
  13
  14 fn f1(x: &mut isize) {
  15     *x = 1; // no error
  16 }
  17
  18 fn f2() {
  19     let mut x: isize = 3; //~ ERROR: value assigned to `x` is never read
  20     x = 4;
  21     x.clone();
  22 }
  23
  24 fn f3() {
  25     let mut x: isize = 3;
  26     x.clone();
  27     x = 4; //~ ERROR: value assigned to `x` is never read
  28 }
  29
  30 fn f4(mut x: i32) { //~ ERROR: value passed to `x` is never read
  31     x = 4;
  32     x.clone();
  33 }
  34
  35 fn f5(mut x: i32) {
  36     x.clone();
  37     x = 4; //~ ERROR: value assigned to `x` is never read
  38 }
  39
  40 fn main() {}