Union with only []type fields causes compile error #25944

const std = @import("std");

// compile error
const Foo = union(enum) {
    opt1: []const type,
    opt2: []const type,
};

pub fn main() !void {
    const foo1: Foo = Foo{ .opt1 = &.{} };
    std.debug.print("foo1: {any}\n", .{foo1});

    const foo2: Foo = Foo{ .opt2 = &.{} };
    std.debug.print("foo2: {any}\n", .{foo2});
}

// works
const Foo = union(enum) {
    opt1: []const i32,
    opt2: []const type,
};

// works
const Foo = union(enum) {
    opt1: []const type,
};

// works (work-around)
const Foo = union(enum(usize)) {
    opt1: []const type,
    opt2: []const type,
};