Comparison of fixed point numbers delivers wrong result in some situations

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Comparing some fixed point numbers results always in "false". The original fixed library does not have this problem. Further information and code example below.

System
OS: # 86~20.04.1-Ubuntu - Kernel 5.4.0-77-generic - x86_64 GNU/Linux
CPU: Ryzen 5 3600
RAM: 32 GB - 2x D416GB 3600-17 Viper Steel - 0B swap

Minimal example
tested with rustc nightly-2021-03-10-x86_64-unknown-linux-gnu and stable-x86_64-unknown-linux-gnu.

using substrate-fixed @ b33d186:

[dependencies.fixed]
default-features = false
git = "https://github.com/encointer/substrate-fixed"
package = "substrate-fixed"
rev = "b33d186888c60f38adafcfc0ec3a21aab263aef1"

use fixed::{FixedI128, FixedU128, types::extra::U64};
use fixed::traits::ToFixed;

fn main() {
	let max_u128u64 = <FixedU128<U64>>::max_value();
	let max_i128u64 = <FixedI128<U64>>::max_value();

	println!("{} < {}: {}", max_i128u64, max_u128u64, max_i128u64 < max_u128u64);
	println!("{} == {}: {}", max_i128u64, max_u128u64, max_i128u64 == max_u128u64);
	println!("{} > {}: {}", max_i128u64, max_u128u64, max_i128u64 > max_u128u64);
	println!("");
	let some_i128u64: FixedI128<U64> = 123456790.to_fixed();
	println!("{} < {}: {}", some_i128u64, max_u128u64, some_i128u64 < max_u128u64);
	println!("{} == {}: {}", some_i128u64, max_u128u64, some_i128u64 == max_u128u64);
	println!("{} > {}: {}", some_i128u64, max_u128u64, some_i128u64 > max_u128u64);
}

9223372036854775807.99999999999999999995 < 18446744073709551615.99999999999999999995: false
9223372036854775807.99999999999999999995 == 18446744073709551615.99999999999999999995: false
9223372036854775807.99999999999999999995 > 18446744073709551615.99999999999999999995: false

123456790 < 18446744073709551615.99999999999999999995: false
123456790 == 18446744073709551615.99999999999999999995: false
123456790 > 18446744073709551615.99999999999999999995: false

The same with the original fixed library @ v1.9.0:

use fixed::{FixedI128, FixedU128, types::extra::U64};
use fixed::traits::ToFixed;

fn main() {
	let max_u128u64 = <FixedU128<U64>>::from_bits(0xFFFF_FFFF_FFFF_FFFF_FFFF_FFFF_FFFF_FFFF);
	let max_i128u64 = <FixedI128<U64>>::from_bits(0x7FFF_FFFF_FFFF_FFFF_FFFF_FFFF_FFFF_FFFF);

	println!("{} < {}: {}", max_i128u64, max_u128u64, max_i128u64 < max_u128u64);
	println!("{} == {}: {}", max_i128u64, max_u128u64, max_i128u64 == max_u128u64);
	println!("{} > {}: {}", max_i128u64, max_u128u64, max_i128u64 > max_u128u64);
	println!("");
	let some_i128u64: FixedI128<U64> = 123456790.to_fixed();
	println!("{} < {}: {}", some_i128u64, max_u128u64, some_i128u64 < max_u128u64);
	println!("{} == {}: {}", some_i128u64, max_u128u64, some_i128u64 == max_u128u64);
	println!("{} > {}: {}", some_i128u64, max_u128u64, some_i128u64 > max_u128u64);
}

9223372036854775807.99999999999999999995 < 18446744073709551615.99999999999999999995: true
9223372036854775807.99999999999999999995 == 18446744073709551615.99999999999999999995: false
9223372036854775807.99999999999999999995 > 18446744073709551615.99999999999999999995: false

123456790 < 18446744073709551615.99999999999999999995: true
123456790 == 18446744073709551615.99999999999999999995: false
123456790 > 18446744073709551615.99999999999999999995: false