[ModernMech]

It’s not that they embed probabilistic behavior per se. But more like they are chaotic systems, in that a slight change of input can drastically change the output. But ideally, good compiler design is idempotent — given the same input, the output should always be the same. If that were not generally true, programming would be much harder than it is.

[glitchc]

No, it can also vary on the input. The -ffast-math flag in gcc is a good example.