https://issues.dlang.org/show_bug.cgi?id=23598
--- Comment #6 from Walter Bright <[email protected]> --- What seems to be happening is the first time it goes through `template sort`, it cannot set `aliasdecl` because the two `alias sort` assignments are hidden behind conditional compilation. Hence `aliasdecl` is null. So, in semantic for `struct String` it encounters `SortedItems.length`. The `aliasdecl` is null, so `SortedItems` becomes `sort!(...)` which becomes `void` and there is no `length` for `void`. --
