> As far as I know, since the uwu function was declared with x and y as restrict, the way uwu is called in main is undefined behavior.
In the first example the integer-cast derivative of the second pointer does alias the first but isn't used to access either object, therefore there is (or should be) no UB.
> I guess if I am wrong its because `restrict` ...
The `restrict` keyword was -IIUC- specifically intended to make it possible to write functions like `memcpy()` w/ optimizations that are made possible by knowing that the pointed-to objects do not overlap. The semantics of that are crystal clear in a hand-wavy way, but... very difficult to nail down exactly.
With a hand-wavy definition of `restrict` it's pretty clear that the first `uwu()` is perfectly fine and has no UB.
In the first example the integer-cast derivative of the second pointer does alias the first but isn't used to access either object, therefore there is (or should be) no UB.
> I guess if I am wrong its because `restrict` ...
The `restrict` keyword was -IIUC- specifically intended to make it possible to write functions like `memcpy()` w/ optimizations that are made possible by knowing that the pointed-to objects do not overlap. The semantics of that are crystal clear in a hand-wavy way, but... very difficult to nail down exactly.
With a hand-wavy definition of `restrict` it's pretty clear that the first `uwu()` is perfectly fine and has no UB.