1const U = union {
 2    comptime a: u32 = 1,
 3};
 4const E = enum {
 5    comptime a = 1,
 6};
 7const P = packed struct {
 8    comptime a: u32 = 1,
 9};
10const X = extern struct {
11    comptime a: u32 = 1,
12};
13
14// error
15//
16// :2:5: error: union fields cannot be marked comptime
17// :5:5: error: enum fields cannot be marked comptime
18// :8:5: error: packed struct fields cannot be marked comptime
19// :11:5: error: extern struct fields cannot be marked comptime