1 #![feature(const_raw_ptr_deref)]
2 #![feature(const_ptr_offset_from)]
3 #![feature(ptr_offset_from)]
11 pub const DIFFERENT_ALLOC: usize = {
13 let uninit = std::mem::MaybeUninit::<Struct>::uninit();
14 let base_ptr: *const Struct = &uninit as *const _ as *const Struct;
15 let uninit2 = std::mem::MaybeUninit::<Struct>::uninit();
16 let field_ptr: *const Struct = &uninit2 as *const _ as *const Struct;
17 let offset = unsafe { field_ptr.offset_from(base_ptr) };
21 pub const NOT_PTR: usize = {
23 unsafe { (42 as *const u8).offset_from(&5u8) as usize }
26 pub const NOT_MULTIPLE_OF_SIZE: isize = {
28 let data = [5u8, 6, 7];
29 let base_ptr = data.as_ptr();
30 let field_ptr = &data[1] as *const u8 as *const u16;
31 unsafe { field_ptr.offset_from(base_ptr as *const u16) }
34 pub const OFFSET_FROM_NULL: isize = {
36 let ptr = 0 as *const u8;
37 unsafe { ptr.offset_from(ptr) }
40 pub const DIFFERENT_INT: isize = { // offset_from with two different integers: like DIFFERENT_ALLOC
42 let ptr1 = 8 as *const u8;
43 let ptr2 = 16 as *const u8;
44 unsafe { ptr2.offset_from(ptr1) }