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

52 lines
1.4 KiB
Rust

//@ normalize-stderr-test: "\d+ bits" -> "N bits"
// Tests that `transmute` cannot be called on types of different size.
#![allow(warnings)]
#![feature(specialization)]
use std::mem::transmute;
unsafe fn f() {
let _: i8 = transmute(16i16);
//~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
}
unsafe fn g<T>(x: &T) {
let _: i8 = transmute(x);
//~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
}
trait Specializable { type Output; }
impl<T> Specializable for T {
default type Output = u16;
}
unsafe fn specializable<T>(x: u16) -> <T as Specializable>::Output {
transmute(x)
//~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
}
#[repr(align(32))]
struct OverAlignZST;
pub struct PtrAndOverAlignZST<T: ?Sized> {
_inner: *mut T,
_other: OverAlignZST,
}
pub unsafe fn shouldnt_work<T: ?Sized>(from: *mut T) -> PtrAndOverAlignZST<T> {
transmute(from)
//~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
}
pub struct PtrAndEmptyArray<T: ?Sized> {
_inner: *mut T,
_other: [*mut T; 0],
}
pub unsafe fn shouldnt_work2<T: ?Sized>(from: *mut T) -> PtrAndEmptyArray<T> {
std::mem::transmute(from)
//~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
}
fn main() {}