const REG_ADDR: *mut u8 = 0x5f3759df as *mut u8; const VALUE: u8 = unsafe { *REG_ADDR }; //~^ ERROR dereferencing raw mutable pointers in constants is unstable const unsafe fn unreachable() -> ! { use std::convert::Infallible; const INFALLIBLE: *mut Infallible = &[] as *const [Infallible] as *const _ as _; match *INFALLIBLE {} //~^ ERROR dereferencing raw mutable pointers in constant functions is unstable const BAD: () = unsafe { match *INFALLIBLE {} }; //~^ ERROR dereferencing raw mutable pointers in constants is unstable } fn main() { }