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71 lines
2.7 KiB
Rust
71 lines
2.7 KiB
Rust
// ignore-tidy-linelength
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// Strip out raw byte dumps to make comparison platform-independent:
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//@ normalize-stderr-test "(the raw bytes of the constant) \(size: [0-9]*, align: [0-9]*\)" -> "$1 (size: $$SIZE, align: $$ALIGN)"
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//@ normalize-stderr-test "([0-9a-f][0-9a-f] |╾─*ALLOC[0-9]+(\+[a-z0-9]+)?(<imm>)?─*╼ )+ *│.*" -> "HEX_DUMP"
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#![allow(invalid_value)]
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use std::mem;
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#[repr(C)]
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union MaybeUninit<T: Copy> {
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uninit: (),
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init: T,
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}
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const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) };
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//~^ ERROR it is undefined behavior to use this value
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//~| constructing invalid value: encountered an unaligned reference (required 2 byte alignment but found 1)
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const UNALIGNED_BOX: Box<u16> = unsafe { mem::transmute(&[0u8; 4]) };
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//~^ ERROR it is undefined behavior to use this value
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//~| constructing invalid value: encountered an unaligned box (required 2 byte alignment but found 1)
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const NULL: &u16 = unsafe { mem::transmute(0usize) };
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//~^ ERROR it is undefined behavior to use this value
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const NULL_BOX: Box<u16> = unsafe { mem::transmute(0usize) };
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//~^ ERROR it is undefined behavior to use this value
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// It is very important that we reject this: We do promote `&(4 * REF_AS_USIZE)`,
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// but that would fail to compile; so we ended up breaking user code that would
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// have worked fine had we not promoted.
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const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) };
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//~^ ERROR evaluation of constant value failed
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const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }];
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//~^ ERROR evaluation of constant value failed
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const REF_AS_USIZE_BOX_SLICE: Box<[usize]> = unsafe { mem::transmute::<&[usize], _>(&[mem::transmute(&0)]) };
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//~^ ERROR evaluation of constant value failed
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const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) };
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//~^ ERROR it is undefined behavior to use this value
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const USIZE_AS_BOX: Box<u8> = unsafe { mem::transmute(1337usize) };
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//~^ ERROR it is undefined behavior to use this value
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const UNINIT_PTR: *const i32 = unsafe { MaybeUninit { uninit: () }.init };
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//~^ ERROR evaluation of constant value failed
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//~| uninitialized
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const NULL_FN_PTR: fn() = unsafe { mem::transmute(0usize) };
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//~^ ERROR it is undefined behavior to use this value
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const UNINIT_FN_PTR: fn() = unsafe { MaybeUninit { uninit: () }.init };
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//~^ ERROR evaluation of constant value failed
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//~| uninitialized
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const DANGLING_FN_PTR: fn() = unsafe { mem::transmute(13usize) };
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//~^ ERROR it is undefined behavior to use this value
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const DATA_FN_PTR: fn() = unsafe { mem::transmute(&13) };
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//~^ ERROR it is undefined behavior to use this value
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const UNALIGNED_READ: () = unsafe {
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let x = &[0u8; 4];
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let ptr = x.as_ptr().cast::<u32>();
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ptr.read(); //~ inside `UNALIGNED_READ`
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};
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fn main() {}
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