> How would Rust fix this? [...] I guess the answer is that you wouldn't do the memcpy like that in idiomatic Rust - you'd use some higher level construct that

> How would Rust fix this? [...] I guess the answer is that you wouldn't do the memcpy like that in idiomatic Rust - you'd use some higher level construct that gives the compiler more chance to catch your errors. Yes, that's the trick: it will be caught not in the u8 overflow, but either in the memcpy equivalent (which is "dst.copy_from_slice(src)"), or in the slice manipulation before it. What happens is that slices in Rust are represented by a "fat pointer", a pair of the starting address and the length, and both the "copy_from_slice" method and the index/index_mut operator check the bounds before doing the operation. (You could do things using "unsafe" and raw pointers, which have only the starting address without the length, but in idiomatic Rust you'd use slices most of the time.)