src/tools/miri/tests/pass/partially-uninit.rs

   1 use std::mem::{self, MaybeUninit};
   2
   3 #[repr(C)]
   4 #[derive(Copy, Clone, Debug, PartialEq)]
   5 struct Demo(bool, u16);
   6
   7 fn main() {
   8     unsafe {
   9         // Transmute-round-trip through a type with Scalar layout is lossless.
  10         // This is tricky because that 'scalar' is *partially* uninitialized.
  11         let x = Demo(true, 3);
  12         let y: MaybeUninit<u32> = mem::transmute(x);
  13         assert_eq!(x, mem::transmute(y));
  14     }
  15 }