1 // compile-flags: --crate-type=lib
2 // normalize-stderr-32bit: "8 bytes" -> "$$TWO_WORDS bytes"
3 // normalize-stderr-64bit: "16 bytes" -> "$$TWO_WORDS bytes"
4 // normalize-stderr-32bit: "size 4" -> "size $$WORD"
5 // normalize-stderr-64bit: "size 8" -> "size $$WORD"
9 const_raw_ptr_comparison,
12 const FOO: &usize = &42;
15 (eq, $a:expr, $b:expr) => {
17 assert!(std::intrinsics::ptr_guaranteed_cmp($a as *const u8, $b as *const u8) == 1);
19 (ne, $a:expr, $b:expr) => {
21 assert!(std::intrinsics::ptr_guaranteed_cmp($a as *const u8, $b as *const u8) == 0);
23 (!, $a:expr, $b:expr) => {
25 assert!(std::intrinsics::ptr_guaranteed_cmp($a as *const u8, $b as *const u8) == 2);
31 check!(ne, FOO as *const _, 0);
32 check!(ne, unsafe { (FOO as *const usize).offset(1) }, 0);
33 check!(ne, unsafe { (FOO as *const usize as *const u8).offset(3) }, 0);
35 // We want pointers to be equal to themselves, but aren't checking this yet because
36 // there are some open questions (e.g. whether function pointers to the same function
37 // compare equal, they don't necessarily at runtime).
38 // The case tested here should work eventually, but does not work yet.
39 check!(!, FOO as *const _, FOO as *const _);
42 ///////////////////////////////////////////////////////////////////////////////
43 // If any of the below start compiling, make sure to add a `check` test for it.
44 // These invocations exist as canaries so we don't forget to check that the
45 // behaviour of `guaranteed_eq` and `guaranteed_ne` is still correct.
46 // All of these try to obtain an out of bounds pointer in some manner. If we
47 // can create out of bounds pointers, we can offset a pointer far enough that
48 // at runtime it would be zero and at compile-time it would not be zero.
50 const _: *const usize = unsafe { (FOO as *const usize).offset(2) };
53 unsafe { std::ptr::addr_of!((*(FOO as *const usize as *const [u8; 1000]))[999]) };
54 //~^ ERROR evaluation of constant value failed
57 const _: usize = unsafe { std::mem::transmute::<*const usize, usize>(FOO) + 4 };
58 //~^ ERROR evaluation of constant value failed
59 //~| unable to turn pointer into raw bytes
61 const _: usize = unsafe { *std::mem::transmute::<&&usize, &usize>(&FOO) + 4 };
62 //~^ ERROR evaluation of constant value failed
63 //~| unable to turn pointer into raw bytes