Bool literals gt comparison causes a strange warning

[tldrlol]

The following program causes a strange warning when run on rust playground nightly:

fn main() {
    true > false;
}

warning: can't do this op on bools, #[warn(const_err)] on by default
 --> <anon>:2:5
  |
2 |     true > false;
  |     ^^^^^^^^^^^^

However this version compiles cleanly:

fn main() {
    let t = true;
    t > false;
}

[durka]

cc @oli-obk