Comment by steveklabnik

It's true that care still needs to be taken. Many people in C are critical of strict aliasing (Linus as a major example) while not being too worried about the dangers when punning. Strict aliasing adds additional things you need to worry about on top of the representation issues. It's a worry you have in C (unless you use a flag and write non-standards conforming code) that you don't have in Rust.