### What it does Checks for for-loops that manually copy items between slices that could be optimized by having a memcpy. ### Why is this bad? It is not as fast as a memcpy. ### Example ``` for i in 0..src.len() { dst[i + 64] = src[i]; } ``` Use instead: ``` dst[64..(src.len() + 64)].clone_from_slice(&src[..]); ```