| // EMIT_MIR_FOR_EACH_PANIC_STRATEGY | |
| // This attempts to modify `x.1` via a pointer derived from `addr_of_mut!(x.0)`. | |
| // According to Miri, that is UB. However, T-opsem has not finalized that | |
| // decision and as such we cannot rely on it in optimizations. Consequently, | |
| // DataflowConstProp must treat the `addr_of_mut!(x.0)` as potentially being | |
| // used to modify `x.1` - if it did not, then it might incorrectly assume that it | |
| // can infer the value of `x.1` at the end of this function. | |
| //@ test-mir-pass: DataflowConstProp | |
| // EMIT_MIR sibling_ptr.main.DataflowConstProp.diff | |
| // CHECK-LABEL: fn main( | |
| fn main() { | |
| // CHECK: debug x1 => [[x1:_.*]]; | |
| let mut x: (u8, u8) = (0, 0); | |
| unsafe { | |
| let p = std::ptr::addr_of_mut!(x.0); | |
| *p.add(1) = 1; | |
| } | |
| // CHECK: [[x1]] = copy ({{_.*}}.1: u8); | |
| let x1 = x.1; // should not be propagated | |
| } |