1fn returns() usize {
 2    return 2;
 3}
 4export fn f1() void {
 5    while (true) returns();
 6}
 7export fn f2() void {
 8    var x: ?i32 = null;
 9    _ = &x;
10    while (x) |_| returns();
11}
12export fn f3() void {
13    var x: anyerror!i32 = error.Bad;
14    _ = &x;
15    while (x) |_| returns() else |_| unreachable;
16}
17export fn f4() void {
18    var a = true;
19    _ = &a;
20    while (a) {} else true;
21}
22export fn f5() void {
23    var a = true;
24    _ = &a;
25    const foo = while (a) returns() else true;
26    _ = foo;
27}
28
29// error
30//
31// :5:25: error: value of type 'usize' ignored
32// :5:25: note: all non-void values must be used
33// :5:25: note: to discard the value, assign it to '_'
34// :10:26: error: value of type 'usize' ignored
35// :10:26: note: all non-void values must be used
36// :10:26: note: to discard the value, assign it to '_'
37// :15:26: error: value of type 'usize' ignored
38// :15:26: note: all non-void values must be used
39// :15:26: note: to discard the value, assign it to '_'
40// :20:23: error: value of type 'bool' ignored
41// :20:23: note: all non-void values must be used
42// :20:23: note: to discard the value, assign it to '_'
43// :25:34: error: value of type 'usize' ignored
44// :25:34: note: all non-void values must be used
45// :25:34: note: to discard the value, assign it to '_'