Properly compare unequal function pointers #581
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tests/run-pass/fn_ptr_comparison.rs
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| fn main() { | ||
| assert!(return_fn_ptr() != f); |
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Can you add this to the existing fn ptr test instead?
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| fn main() { | ||
| assert!(return_fn_ptr() == f); //~ ERROR assertion failed |
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What is the purpose of this test? We already test elsewhere that assert!(false) fails, don't we?
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I just wanted to make sure we're getting the right error. But I guess the run-pass test kinda guarantees that
| // Two in-bounds pointers, we can compare across allocations | ||
| left == right | ||
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| let check = |ptr: Pointer<Borrow>| match self.memory().get(ptr.alloc_id) { |
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This is not nice. :/
For once, it's not correct: A pointer into a function allocation is only in-bounds if its offset is 0.
But also, the previous behavior that memory().check_bounds would accept offset-0-size-0 pointers into function allocations was fully intended. These pointers are in-bounds. There is nothing wrong with a &() pointing to a function allocation. So I don't think fixing this here is how we want to proceed.
For example, pointer_offset_inbounds now also fails to compute a 0-offset on a function pointer. This affects every user of the old check_bounds method that was converted to memory().get.
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I can reintroduce the check_bounds method on Memory
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Yeah I think that would make most sense.
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Superseded by #587 |
fixes #577