tests/ui/transmute/transmute-different-sizes.rs

   1 // normalize-stderr-test "\d+ bits" -> "N bits"
   2
   3 // Tests that `transmute` cannot be called on types of different size.
   4
   5 #![allow(warnings)]
   6 #![feature(specialization)]
   7
   8 use std::mem::transmute;
   9
  10 unsafe fn f() {
  11     let _: i8 = transmute(16i16);
  12     //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
  13 }
  14
  15 unsafe fn g<T>(x: &T) {
  16     let _: i8 = transmute(x);
  17     //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
  18 }
  19
  20 trait Specializable { type Output; }
  21
  22 impl<T> Specializable for T {
  23     default type Output = u16;
  24 }
  25
  26 unsafe fn specializable<T>(x: u16) -> <T as Specializable>::Output {
  27     transmute(x)
  28     //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
  29 }
  30
  31 fn main() {}