1const Letter = enum {
 2    A,
 3    B,
 4    C,
 5};
 6const Payload = union(Letter) {
 7    A: i32,
 8    B: f64,
 9};
10export fn entry() usize {
11    return @sizeOf(Payload);
12}
13
14// error
15//
16// :6:17: error: enum field(s) missing in union
17// :4:5: note: field 'C' missing, declared here
18// :1:16: note: enum declared here