better handling of lazy structs

this case works now:

```zig
const A = struct {
    b_list_pointer: *const []B,
};
const B = struct {
    a_pointer: *const A,
};

const b_list: []B = [_]B{};
const a = A{ .b_list_pointer = &b_list };
const obj = B{ .a_pointer = &a };
```
ac4dd9d665Andrew Kelley committed on 8/23/2019, 7:54:51 PMparentbe0a9a7
5 files changedLine totals unavailable