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//@ run-pass
// Transmuting to/from ZSTs that contain generics.
#![feature(transmute_generic_consts)]
// Verify non-generic ZST -> generic ZST transmute
unsafe fn cast_zst0<T>(from: ()) -> [T; 0] {
::std::mem::transmute::<(), [T; 0]>(from)
}
// Verify generic ZST -> non-generic ZST transmute
unsafe fn cast_zst1<T>(from: [T; 0]) -> () {
::std::mem::transmute::<[T; 0], ()>(from)
}
// Verify transmute with generic compound types
unsafe fn cast_zst2<T>(from: ()) -> [(T, T); 0] {
::std::mem::transmute::<(), [(T, T); 0]>(from)
}
// Verify transmute with ZST propagation through arrays
unsafe fn cast_zst3<T>(from: ()) -> [[T; 0]; 8] {
::std::mem::transmute::<(), [[T; 0]; 8]>(from)
}
// Verify transmute with an extra ZST field
pub struct PtrAndZst<T: ?Sized> {
_inner: *mut T,
_other: (),
}
pub unsafe fn cast_ptr<T: ?Sized>(from: *mut T) -> PtrAndZst<T> {
std::mem::transmute(from)
}
pub fn main() {
unsafe {
let _: [u32; 0] = cast_zst0(());
let _ = cast_zst1::<u32>([]);
let _: [(u32, u32); 0] = cast_zst2(());
let _: [[u32; 0]; 8] = cast_zst3(());
cast_ptr(&mut 42);
};
}
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