src/test/compile-fail/transmute-from-fn-item-types-lint.rs

   1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![deny(transmute_from_fn_item_types)]
  12
  13 use std::mem;
  14
  15 unsafe fn foo() -> (isize, *const (), Option<fn()>) {
  16     let i = mem::transmute(bar);
  17     //~^ ERROR is now zero-sized and has to be cast to a pointer before transmuting
  18     //~^^ ERROR was previously accepted
  19
  20     let p = mem::transmute(foo);
  21     //~^ ERROR is now zero-sized and has to be cast to a pointer before transmuting
  22     //~^^ ERROR was previously accepted
  23
  24     let of = mem::transmute(main);
  25     //~^ ERROR is now zero-sized and has to be cast to a pointer before transmuting
  26     //~^^ ERROR was previously accepted
  27
  28     (i, p, of)
  29 }
  30
  31 unsafe fn bar() {
  32     mem::transmute::<_, *mut ()>(foo);
  33     //~^ ERROR is now zero-sized and has to be cast to a pointer before transmuting
  34     //~^^ ERROR was previously accepted
  35
  36     mem::transmute::<_, fn()>(bar);
  37     //~^ ERROR is now zero-sized and has to be cast to a pointer before transmuting
  38     //~^^ ERROR was previously accepted
  39
  40     // No error if a coercion would otherwise occur.
  41     mem::transmute::<fn(), usize>(main);
  42 }
  43
  44 fn main() {
  45     unsafe {
  46         foo();
  47         bar();
  48     }
  49 }