Generating new structs is free in Rust. There is only cost if you need to send it somewhere and the layout differs from the original. Since `transmute` will be

Generating new structs is free in Rust. There is only cost if you need to send it somewhere and the layout differs from the original. Since `transmute` will be undefined behaviour if the layout differs you will only be saving cost if you would be invoking undefined behaviour. I recommend checking the generated asm and reporting a missed-optimization bug if it differs.