PowerToys Run Calculator plugin Incorrectly displays results for 2 ^ 64

[reed-hayden]

Microsoft PowerToys version

0.79.0

Installation method

WinGet

Running as admin

No

Area(s) with issue?

PowerToys Run

Steps to reproduce

1. Open PowerToys Run
2. Enter 2 ^ 64
3. Observe result

The picture below show both the native calculator app and powertoys run in the same image

✔️ Expected Behavior

The result should show 18446744073709551616

❌ Actual Behavior

The result shown is: 18446744073709600000

Note: You can also get incorrect answers by typing in 2^ 51, 2^ 52 ... etc

Other Software

No response

[davidegiacometti]

It looks like an overflow issue.

[htcfreek]

This is a limitation of the "mages" calculation library. It's known but I don't know if we have an existing tracking issue.

It is caused by the number data types used in the library. There were changes in the past to improve the correctness but more correctness is impossible from what I know.

[arphox]

I also experienced this when trying to calculate 2^63-1 to get System.Int64 maxvalue.

9223372036854780000 is what the tool wrote, but
9223372036854775807 is the correct value.