| // 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 |
| } |
