src/test/ui/transmute/transmute-padding-ice.rs

   1 #![crate_type = "lib"]
   2 #![feature(transmutability)]
   3 #![allow(dead_code)]
   4
   5 mod assert {
   6     use std::mem::{Assume, BikeshedIntrinsicFrom};
   7     pub struct Context;
   8
   9     pub fn is_maybe_transmutable<Src, Dst>()
  10     where
  11         Dst: BikeshedIntrinsicFrom<
  12             Src,
  13             Context,
  14             { Assume { alignment: true, lifetimes: true, safety: true, validity: true } },
  15         >,
  16     {
  17     }
  18 }
  19
  20 fn test() {
  21     #[repr(C, align(2))]
  22     struct A(u8, u8);
  23
  24     #[repr(C)]
  25     struct B(u8, u8);
  26
  27     assert::is_maybe_transmutable::<B, A>();
  28     //~^ ERROR cannot be safely transmuted
  29 }