b38a86f4d7
This reverts commit1eeb8e8b15, reversing changes made to324bf2b9fd. Unfortunately the assert desugaring change is not backwards compatible, see RUST-145770. Code such as ```rust #[derive(Debug)] struct F { data: bool } impl std::ops::Not for F { type Output = bool; fn not(self) -> Self::Output { !self.data } } fn main() { let f = F { data: true }; assert!(f); } ``` would be broken by the assert desugaring change. We may need to land the change over an edition boundary, or limit the editions that the desugaring change impacts.
28 lines
919 B
Rust
28 lines
919 B
Rust
//@ run-pass
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//@ compile-flags: -C debug-assertions
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#[repr(packed)]
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struct Misaligner {
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_head: u8,
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tail: u64,
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}
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fn main() {
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let memory = [Misaligner { _head: 0, tail: 0}, Misaligner { _head: 0, tail: 0}];
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// Test that we can use addr_of! to get the address of a packed member which according to its
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// type is not aligned, but because it is a projection from a packed type is a valid place.
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let ptr0 = std::ptr::addr_of!(memory[0].tail);
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let ptr1 = std::ptr::addr_of!(memory[0].tail);
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// Even if ptr0 happens to be aligned by chance, ptr1 is not.
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assert!(!ptr0.is_aligned() || !ptr1.is_aligned());
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// And also test that we can get the addr of a packed struct then do a member read from it.
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unsafe {
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let ptr = std::ptr::addr_of!(memory[0]);
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let _tail = (*ptr).tail;
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let ptr = std::ptr::addr_of!(memory[1]);
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let _tail = (*ptr).tail;
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}
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}
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