25 lines
754 B
Rust
25 lines
754 B
Rust
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#![feature(const_mut_refs)]
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#![feature(const_fn)]
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#![feature(raw_ref_op)]
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const NULL: *mut i32 = std::ptr::null_mut();
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const A: *const i32 = &4;
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// It could be made sound to allow it to compile,
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// but we do not want to allow this to compile,
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// as that would be an enormous footgun in oli-obk's opinion.
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const B: *mut i32 = &mut 4; //~ ERROR mutable references are not allowed
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// Could be ok, but the same analysis that prevents the mutable one above will also bail out here
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// Using a block with some complex content, because just `&45` would get promoted,
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// which is not what we want to test here.
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const C: *const i32 = &{
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let mut x = 42;
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x += 3;
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x
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};
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fn main() {
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println!("{}", unsafe { *A });
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unsafe { *B = 4 } // Bad news
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}
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