1 #![feature(const_raw_ptr_deref)]
2 #![feature(const_ptr_offset_from)]
10 pub const DIFFERENT_ALLOC: usize = {
12 let uninit = std::mem::MaybeUninit::<Struct>::uninit();
13 let base_ptr: *const Struct = &uninit as *const _ as *const Struct;
14 let uninit2 = std::mem::MaybeUninit::<Struct>::uninit();
15 let field_ptr: *const Struct = &uninit2 as *const _ as *const Struct;
16 let offset = unsafe { field_ptr.offset_from(base_ptr) };
20 pub const NOT_PTR: usize = {
22 unsafe { (42 as *const u8).offset_from(&5u8) as usize }
25 pub const NOT_MULTIPLE_OF_SIZE: isize = {
27 let data = [5u8, 6, 7];
28 let base_ptr = data.as_ptr();
29 let field_ptr = &data[1] as *const u8 as *const u16;
30 unsafe { field_ptr.offset_from(base_ptr as *const u16) }
33 pub const OFFSET_FROM_NULL: isize = {
35 let ptr = 0 as *const u8;
36 unsafe { ptr.offset_from(ptr) }
39 pub const DIFFERENT_INT: isize = { // offset_from with two different integers: like DIFFERENT_ALLOC
41 let ptr1 = 8 as *const u8;
42 let ptr2 = 16 as *const u8;
43 unsafe { ptr2.offset_from(ptr1) }