issue-21174.rs

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

trait Trait<'a> {
    type A;
    type B;
}

fn foo<'a, T: Trait<'a>>(value: T::A) {
    let new: T::B = unsafe { std::mem::transmute(value) };
//~^ ERROR: transmute called with types of different sizes
}

fn main() { }