Have you heard about the background bug on Android 10? I'm talking about this...

https://xda-developers.com/wallpape...

How the hell does something like that happen?? Who coded that formula without checking it's output boundaries?

if (value > 255){
value = 255;
}

@sudocode Some phones can boot in safe mode.

@sudocode Or I just remove the wallpaper from custom recovery.

> Who coded that formula without checking it's output boundaries?
If nobody thought it would ever exceed them... I'm more surprised that the failure of rendering a wallpaper crashes the whole system.

> buffer overflow crash
You mean ACE, right?

@sbiewald the formula itself "mathematically" never exceeds 255, because it's coefficients are normalized to 1. So if input is 3 value in range(0-255), output will be too.
But they compute each value by itself, then round it, then sum them. So output can get as high as 258. There is a basic math principle that should be tought as one of the first concept in a programming course (as it is in any physics or math course): never round any non-final value if it's not necessary.