From 218caa410aa38c29984be31a5229b9fa717560ee Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:19:13 +0200 Subject: Merging upstream version 1.68.2+dfsg1. Signed-off-by: Daniel Baumann --- tests/ui/consts/const-eval/ub-ref-ptr.rs | 71 ++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 tests/ui/consts/const-eval/ub-ref-ptr.rs (limited to 'tests/ui/consts/const-eval/ub-ref-ptr.rs') diff --git a/tests/ui/consts/const-eval/ub-ref-ptr.rs b/tests/ui/consts/const-eval/ub-ref-ptr.rs new file mode 100644 index 000000000..369e45194 --- /dev/null +++ b/tests/ui/consts/const-eval/ub-ref-ptr.rs @@ -0,0 +1,71 @@ +// ignore-tidy-linelength +// Strip out raw byte dumps to make comparison platform-independent: +// normalize-stderr-test "(the raw bytes of the constant) \(size: [0-9]*, align: [0-9]*\)" -> "$1 (size: $$SIZE, align: $$ALIGN)" +// normalize-stderr-test "([0-9a-f][0-9a-f] |╾─*a(lloc)?[0-9]+(\+[a-z0-9]+)?─*╼ )+ *│.*" -> "HEX_DUMP" +#![allow(invalid_value)] +#![feature(const_ptr_read)] + +use std::mem; + +#[repr(C)] +union MaybeUninit { + uninit: (), + init: T, +} + +const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) }; +//~^ ERROR it is undefined behavior to use this value +//~| constructing invalid value: encountered an unaligned reference (required 2 byte alignment but found 1) + +const UNALIGNED_BOX: Box = unsafe { mem::transmute(&[0u8; 4]) }; +//~^ ERROR it is undefined behavior to use this value +//~| constructing invalid value: encountered an unaligned box (required 2 byte alignment but found 1) + +const NULL: &u16 = unsafe { mem::transmute(0usize) }; +//~^ ERROR it is undefined behavior to use this value + +const NULL_BOX: Box = unsafe { mem::transmute(0usize) }; +//~^ ERROR it is undefined behavior to use this value + + +// It is very important that we reject this: We do promote `&(4 * REF_AS_USIZE)`, +// but that would fail to compile; so we ended up breaking user code that would +// have worked fine had we not promoted. +const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) }; +//~^ ERROR evaluation of constant value failed + +const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }]; +//~^ ERROR evaluation of constant value failed + +const REF_AS_USIZE_BOX_SLICE: Box<[usize]> = unsafe { mem::transmute::<&[usize], _>(&[mem::transmute(&0)]) }; +//~^ ERROR evaluation of constant value failed + +const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) }; +//~^ ERROR it is undefined behavior to use this value + +const USIZE_AS_BOX: Box = unsafe { mem::transmute(1337usize) }; +//~^ ERROR it is undefined behavior to use this value + +const UNINIT_PTR: *const i32 = unsafe { MaybeUninit { uninit: () }.init }; +//~^ ERROR evaluation of constant value failed +//~| uninitialized + +const NULL_FN_PTR: fn() = unsafe { mem::transmute(0usize) }; +//~^ ERROR it is undefined behavior to use this value +const UNINIT_FN_PTR: fn() = unsafe { MaybeUninit { uninit: () }.init }; +//~^ ERROR evaluation of constant value failed +//~| uninitialized +const DANGLING_FN_PTR: fn() = unsafe { mem::transmute(13usize) }; +//~^ ERROR it is undefined behavior to use this value +const DATA_FN_PTR: fn() = unsafe { mem::transmute(&13) }; +//~^ ERROR it is undefined behavior to use this value + + +const UNALIGNED_READ: () = unsafe { + let x = &[0u8; 4]; + let ptr = x.as_ptr().cast::(); + ptr.read(); //~ inside `UNALIGNED_READ` +}; + + +fn main() {} -- cgit v1.2.3