1 //! Test casts for alignment issues
3 #![feature(rustc_private)]
4 #![feature(core_intrinsics)]
7 #[warn(clippy::cast_ptr_alignment)]
10 clippy::unnecessary_operation,
11 clippy::cast_lossless,
16 /* These should be warned against */
18 // cast to more-strictly-aligned type
19 (&1u8 as *const u8) as *const u16;
20 (&mut 1u8 as *mut u8) as *mut u16;
22 // cast to more-strictly-aligned type, but with the `pointer::cast` function.
23 (&1u8 as *const u8).cast::<u16>();
24 (&mut 1u8 as *mut u8).cast::<u16>();
26 /* These should be ok */
30 // cast to less-strictly-aligned type
31 (&1u16 as *const u16) as *const u8;
32 (&mut 1u16 as *mut u16) as *mut u8;
33 // For c_void, we should trust the user. See #2677
34 (&1u32 as *const u32 as *const std::os::raw::c_void) as *const u32;
35 (&1u32 as *const u32 as *const libc::c_void) as *const u32;
36 // For ZST, we should trust the user. See #4256
37 (&1u32 as *const u32 as *const ()) as *const u32;
40 let mut data = [0u8, 0u8];
42 let ptr = &data as *const [u8; 2] as *const u8;
43 let _ = (ptr as *const u16).read_unaligned();
44 let _ = core::ptr::read_unaligned(ptr as *const u16);
45 let _ = core::intrinsics::unaligned_volatile_load(ptr as *const u16);
46 let ptr = &mut data as *mut [u8; 2] as *mut u8;
47 (ptr as *mut u16).write_unaligned(0);
48 core::ptr::write_unaligned(ptr as *mut u16, 0);
49 core::intrinsics::unaligned_volatile_store(ptr as *mut u16, 0);