1const U = union {
 2    foo: u32,
 3    foo: u32,
 4};
 5
 6export fn entry() void {
 7    const u: U = .{ .foo = 100 };
 8    _ = u;
 9}
10
11// error
12//
13// :2:5: error: duplicate union member name 'foo'
14// :3:5: note: duplicate name here
15// :1:11: note: union declared here