nested packed struct incorrect behavior

[archaistvolts]

Zig Version

0.11.0-dev.1577+11cc1c16f

Steps to Reproduce and Observed Behavior

the failing tests are marked with // this fails. the following struct field configuration manifests the issue.

const std = @import("std");

pub const Options = packed struct {
    foo: bool = false,
    bar: bool = false,
    pretty_print: packed struct {
        enabled: bool = false,
        num_spaces: u4 = 4,
        space_char: enum { space, tab } = .space,
        indent: u8 = 0,
    } = .{},
    baz: bool = false,
};
test {
    var opts = Options{};
    opts.pretty_print.indent += 1;
    // prints 00000000000100001
    std.debug.print("{b:0>17}\n", .{@bitCast(u17, opts)});
    // this fails
    try std.testing.expect(!opts.foo);
    try std.testing.expect(!opts.bar);
    try std.testing.expect(!opts.pretty_print.enabled);
    try std.testing.expectEqual(@as(u4, 4), opts.pretty_print.num_spaces);
    // this fails. is actually 0
    try std.testing.expectEqual(@as(u8, 1), opts.pretty_print.indent);
    try std.testing.expect(!opts.baz);
}

other configurations don't seem to manifest this issue. ie moving the nested struct to first position fixes the issue - atleast for the nested fields. i haven't checked any of the other outer fields after moving the nested struct to the top.

Expected Behavior

test pass

[codethief]

Could this be related to #14200 ?