Structs containing a pointer to array of @This() fails (struct depends on itself)

[tnorth]

Creating a struct containing an array of pointers to itself works.
However, creating a struct containing a pointer to an array of structs of the same type fails with the error error: struct 'Bar' depends on itself

const Foo = struct {
    child: [2]*@This(), // Array of 2 pointers to a struct Foo, works. 
};

const Bar = struct {
    child: ?*[2]@This(), // Optional pointer to an array of two struct Bar, fails.
};

pub fn main() !void {
    var foo : Foo = undefined; 
    const foo2 = Foo {.child = [2]*Foo{&foo, &foo}, };

    var bar : Bar = Bar {.child = null};
    const bar2 = Bar {.child = *[2]Bar{&bar, &bar}, };

    return;
}

In struct Bar, removing ? and using bar bar: Bar = undefined also fails with the above error.

Using zig-linux-x86_64-0.8.0-dev.1158+0aef1faa8

[Vexu]

Works in self-hosted when using -fstrip since the LLVM backend recurses infinitely when generating debug info for Bar.

Simple reduction from #12325 (comment)

const Foo = struct {
    ptr: *[1]Foo,
};

test {
    const x: Foo = undefined;
    _ = x;
}