fn f1(x: int) { //~^ WARNING unused variable: `x` } fn f1b(&x: int) { //~^ WARNING unused variable: `x` } fn f2() { let x = 3; //~^ WARNING unused variable: `x` } fn f3() { let mut x = 3; //~^ WARNING variable `x` is assigned to, but never used x += 4; //~^ WARNING value assigned to `x` is never read } fn f3b() { let mut z = 3; //~^ WARNING variable `z` is assigned to, but never used loop { z += 4; } } fn f4() { match some(3) { some(i) => { } none => {} } } // leave this in here just to trigger compile-fail: struct r { let x: (); new() { self.x = (); } drop {} } fn main() { let x = r(); fn@() { copy x; }; //~ ERROR copying a noncopyable value }