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//! Validity must be satisfiable, even if validity is assumed.
#![crate_type = "lib"]
#![feature(transmutability)]
#![allow(dead_code, incomplete_features, non_camel_case_types)]
mod assert {
use std::mem::BikeshedIntrinsicFrom;
pub struct Context;
pub fn is_maybe_transmutable<Src, Dst>()
where
Dst: BikeshedIntrinsicFrom<Src, Context, false, false, true, true>
// validity IS assumed --------------------------------^^^^
{}
}
#[derive(Clone, Copy)] #[repr(u8)] enum Ox00 { V = 0x00 }
#[derive(Clone, Copy)] #[repr(u8)] enum Ox01 { V = 0x01 }
#[derive(Clone, Copy)] #[repr(u8)] enum OxFF { V = 0xFF }
fn test() {
#[repr(C)]
union A {
a: Ox00,
b: OxFF,
}
#[repr(C)]
union B {
c: Ox01,
}
assert::is_maybe_transmutable::<A, B>(); //~ ERROR cannot be safely transmuted
assert::is_maybe_transmutable::<B, A>(); //~ ERROR cannot be safely transmuted
}
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