blob: cbc88bc4d9c382999971f5095021a03641ecd160 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
#![feature(const_ptr_offset_from)]
#![feature(core_intrinsics)]
use std::intrinsics::ptr_offset_from;
#[repr(C)]
struct Struct {
data: u8,
field: u8,
}
pub const DIFFERENT_ALLOC: usize = {
let uninit = std::mem::MaybeUninit::<Struct>::uninit();
let base_ptr: *const Struct = &uninit as *const _ as *const Struct;
let uninit2 = std::mem::MaybeUninit::<Struct>::uninit();
let field_ptr: *const Struct = &uninit2 as *const _ as *const Struct;
let offset = unsafe { ptr_offset_from(field_ptr, base_ptr) }; //~ERROR evaluation of constant value failed
//~| cannot compute offset of pointers into different allocations.
offset as usize
};
pub const NOT_PTR: usize = {
unsafe { (42 as *const u8).offset_from(&5u8) as usize }
};
pub const NOT_MULTIPLE_OF_SIZE: isize = {
let data = [5u8, 6, 7];
let base_ptr = data.as_ptr();
let field_ptr = &data[1] as *const u8 as *const u16;
unsafe { ptr_offset_from(field_ptr, base_ptr as *const u16) } //~ERROR evaluation of constant value failed
//~| 1_isize cannot be divided by 2_isize without remainder
};
pub const OFFSET_FROM_NULL: isize = {
let ptr = 0 as *const u8;
unsafe { ptr_offset_from(ptr, ptr) } //~ERROR evaluation of constant value failed
//~| null pointer is not a valid pointer
};
pub const DIFFERENT_INT: isize = { // offset_from with two different integers: like DIFFERENT_ALLOC
let ptr1 = 8 as *const u8;
let ptr2 = 16 as *const u8;
unsafe { ptr_offset_from(ptr2, ptr1) } //~ERROR evaluation of constant value failed
//~| 0x10 is not a valid pointer
};
fn main() {}
|
