rustc/tests/ui/unsafe/unsafe-fn-deref-ptr.rs

fn f(p: *const u8) -> u8 {
    let _ = *p; //~ ERROR dereference of raw pointer is unsafe
    let _: u8 = *p; //~ ERROR dereference of raw pointer is unsafe
    _ = *p; //~ ERROR dereference of raw pointer is unsafe
    return *p; //~ ERROR dereference of raw pointer is unsafe
}

fn main() {
}