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#![feature(core_intrinsics)]
#![feature(custom_mir)]
// These cases are statically rejected by `mem::transmute`, so we need custom
// MIR to be able to get to constant evaluation.
use std::intrinsics::mir::*;
#[custom_mir(dialect = "runtime", phase = "initial")]
const unsafe fn mir_transmute<T, U>(x: T) -> U {
mir!{
{
RET = CastTransmute(x);
//~^ ERROR evaluation of constant value failed
//~| ERROR evaluation of constant value failed
Return()
}
}
}
const FROM_BIGGER: u16 = unsafe { mir_transmute(123_i32) };
const FROM_SMALLER: u32 = unsafe { mir_transmute(123_i16) };
fn main() {}
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